From patchwork Tue Oct 3 06:24:22 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Li, Xin3" X-Patchwork-Id: 13406829 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A2B9BE75433 for ; Tue, 3 Oct 2023 06:54:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230484AbjJCGym (ORCPT ); Tue, 3 Oct 2023 02:54:42 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37572 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230433AbjJCGyk (ORCPT ); Tue, 3 Oct 2023 02:54:40 -0400 Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.126]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9794FAC; Mon, 2 Oct 2023 23:54:37 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1696316077; x=1727852077; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=5bEJT87B98JS6iQ6LlrNVmLBQuK2BkIiNY3V5ZdVNuo=; b=W42Fi3B0qrpu+FUCrOq9rp/2juU+nc3VMgeLLeJRP6sXaRK8GVR/ktzl Vj1t97gTM6GOhhMa4Epl13W11wo1o/SyiGz8gqKoBFPd0CR6IvXwcG3XX tCKcYhQpn6l5IKVQYz5BQrIgLqC5F7SWvAozUHTeerTDPM+zBikjV0kPS bL4c0wBJdTEDRmBOXQDHbwQkvywasog2rrNYWdRrCIlmSNyn0efwUmHPR YJNceZuxidQSm/UXmLz3OtyZ2Remw7oER/FYjUc/oM6eC3aBicaQCVg+g Eu9YVOHF/yx5bMmjdEDVguUi9KIJMr+UfUoHYTfCzI0sK8OHk/PnhaF7Q A==; X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="367857912" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="367857912" Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Oct 2023 23:54:35 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="1081900894" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="1081900894" Received: from unknown (HELO fred..) ([172.25.112.68]) by fmsmga005.fm.intel.com with ESMTP; 02 Oct 2023 23:54:34 -0700 From: Xin Li To: linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-edac@vger.kernel.org, linux-hyperv@vger.kernel.org, kvm@vger.kernel.org, xen-devel@lists.xenproject.org Cc: tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, luto@kernel.org, pbonzini@redhat.com, seanjc@google.com, peterz@infradead.org, jgross@suse.com, ravi.v.shankar@intel.com, mhiramat@kernel.org, andrew.cooper3@citrix.com, jiangshanlai@gmail.com, nik.borisov@suse.com Subject: [PATCH v12 01/37] x86/cpufeatures: Add the cpu feature bit for WRMSRNS Date: Mon, 2 Oct 2023 23:24:22 -0700 Message-Id: <20231003062458.23552-2-xin3.li@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231003062458.23552-1-xin3.li@intel.com> References: <20231003062458.23552-1-xin3.li@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org WRMSRNS is an instruction that behaves exactly like WRMSR, with the only difference being that it is not a serializing instruction by default. Under certain conditions, WRMSRNS may replace WRMSR to improve performance. Add the CPU feature bit for WRMSRNS. Tested-by: Shan Kang Signed-off-by: Xin Li --- arch/x86/include/asm/cpufeatures.h | 1 + tools/arch/x86/include/asm/cpufeatures.h | 1 + 2 files changed, 2 insertions(+) diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h index 58cb9495e40f..330876d34b68 100644 --- a/arch/x86/include/asm/cpufeatures.h +++ b/arch/x86/include/asm/cpufeatures.h @@ -322,6 +322,7 @@ #define X86_FEATURE_FSRS (12*32+11) /* "" Fast short REP STOSB */ #define X86_FEATURE_FSRC (12*32+12) /* "" Fast short REP {CMPSB,SCASB} */ #define X86_FEATURE_LKGS (12*32+18) /* "" Load "kernel" (userspace) GS */ +#define X86_FEATURE_WRMSRNS (12*32+19) /* "" Non-Serializing Write to Model Specific Register instruction */ #define X86_FEATURE_AMX_FP16 (12*32+21) /* "" AMX fp16 Support */ #define X86_FEATURE_AVX_IFMA (12*32+23) /* "" Support for VPMADD52[H,L]UQ */ #define X86_FEATURE_LAM (12*32+26) /* Linear Address Masking */ diff --git a/tools/arch/x86/include/asm/cpufeatures.h b/tools/arch/x86/include/asm/cpufeatures.h index 798e60b5454b..1b9d86ba5bc2 100644 --- a/tools/arch/x86/include/asm/cpufeatures.h +++ b/tools/arch/x86/include/asm/cpufeatures.h @@ -318,6 +318,7 @@ #define X86_FEATURE_FSRS (12*32+11) /* "" Fast short REP STOSB */ #define X86_FEATURE_FSRC (12*32+12) /* "" Fast short REP {CMPSB,SCASB} */ #define X86_FEATURE_LKGS (12*32+18) /* "" Load "kernel" (userspace) GS */ +#define X86_FEATURE_WRMSRNS (12*32+19) /* "" Non-Serializing Write to Model Specific Register instruction */ #define X86_FEATURE_AMX_FP16 (12*32+21) /* "" AMX fp16 Support */ #define X86_FEATURE_AVX_IFMA (12*32+23) /* "" Support for VPMADD52[H,L]UQ */ #define X86_FEATURE_LAM (12*32+26) /* Linear Address Masking */ From patchwork Tue Oct 3 06:24:23 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Li, Xin3" X-Patchwork-Id: 13406830 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id C4F48E75428 for ; Tue, 3 Oct 2023 06:54:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230526AbjJCGyn (ORCPT ); Tue, 3 Oct 2023 02:54:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37582 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230452AbjJCGyl (ORCPT ); Tue, 3 Oct 2023 02:54:41 -0400 Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.126]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 706DBB0; Mon, 2 Oct 2023 23:54:38 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1696316078; x=1727852078; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=MxQyQabDuj01hP6xHQ5mL2MlMceZ5LcTb8ReoP3KjJA=; b=CK2YHIt64IFZMDSZcLtcvQbtNWV6boBIUHO5BCPyx5gQoucfbLkf/cKJ M2QrakQRx5f9NGJSEP7TyN1RkMl5SpLKpo4zExT8jb4IBIkFE7LHnB0FZ 119e8MAKWhM327DajLEA7Z7AkDzBELL1vFtPdidJ3QYFr5j6rgkNhZhhs PnYgjzRUObzrkDTpwo9IJY2E9ytrUq1r0YVcmWkb+kCTADOvOwd7jr2rp 60rzqAtrF+M6Na0iHk18QPikkraLtf2tH2zun+vVKPdJI8dDD7vsiq7c5 dHt/Bp/oYvgJqzHIyHZzivyXiDmPEbuQkXA0x1Um8EzeHoqYJtNWpDfEZ g==; X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="367857913" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="367857913" Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Oct 2023 23:54:35 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="1081900898" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="1081900898" Received: from unknown (HELO fred..) ([172.25.112.68]) by fmsmga005.fm.intel.com with ESMTP; 02 Oct 2023 23:54:35 -0700 From: Xin Li To: linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-edac@vger.kernel.org, linux-hyperv@vger.kernel.org, kvm@vger.kernel.org, xen-devel@lists.xenproject.org Cc: tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, luto@kernel.org, pbonzini@redhat.com, seanjc@google.com, peterz@infradead.org, jgross@suse.com, ravi.v.shankar@intel.com, mhiramat@kernel.org, andrew.cooper3@citrix.com, jiangshanlai@gmail.com, nik.borisov@suse.com Subject: [PATCH v12 02/37] x86/opcode: Add the WRMSRNS instruction to the x86 opcode map Date: Mon, 2 Oct 2023 23:24:23 -0700 Message-Id: <20231003062458.23552-3-xin3.li@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231003062458.23552-1-xin3.li@intel.com> References: <20231003062458.23552-1-xin3.li@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Add the opcode used by WRMSRNS, which is the non-serializing version of WRMSR and may replace it to improve performance, to the x86 opcode map. Tested-by: Shan Kang Signed-off-by: Xin Li Acked-by: Masami Hiramatsu (Google) --- arch/x86/lib/x86-opcode-map.txt | 2 +- tools/arch/x86/lib/x86-opcode-map.txt | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/x86/lib/x86-opcode-map.txt b/arch/x86/lib/x86-opcode-map.txt index 5168ee0360b2..1efe1d9bf5ce 100644 --- a/arch/x86/lib/x86-opcode-map.txt +++ b/arch/x86/lib/x86-opcode-map.txt @@ -1051,7 +1051,7 @@ GrpTable: Grp6 EndTable GrpTable: Grp7 -0: SGDT Ms | VMCALL (001),(11B) | VMLAUNCH (010),(11B) | VMRESUME (011),(11B) | VMXOFF (100),(11B) | PCONFIG (101),(11B) | ENCLV (000),(11B) +0: SGDT Ms | VMCALL (001),(11B) | VMLAUNCH (010),(11B) | VMRESUME (011),(11B) | VMXOFF (100),(11B) | PCONFIG (101),(11B) | ENCLV (000),(11B) | WRMSRNS (110),(11B) 1: SIDT Ms | MONITOR (000),(11B) | MWAIT (001),(11B) | CLAC (010),(11B) | STAC (011),(11B) | ENCLS (111),(11B) 2: LGDT Ms | XGETBV (000),(11B) | XSETBV (001),(11B) | VMFUNC (100),(11B) | XEND (101)(11B) | XTEST (110)(11B) | ENCLU (111),(11B) 3: LIDT Ms diff --git a/tools/arch/x86/lib/x86-opcode-map.txt b/tools/arch/x86/lib/x86-opcode-map.txt index 5168ee0360b2..1efe1d9bf5ce 100644 --- a/tools/arch/x86/lib/x86-opcode-map.txt +++ b/tools/arch/x86/lib/x86-opcode-map.txt @@ -1051,7 +1051,7 @@ GrpTable: Grp6 EndTable GrpTable: Grp7 -0: SGDT Ms | VMCALL (001),(11B) | VMLAUNCH (010),(11B) | VMRESUME (011),(11B) | VMXOFF (100),(11B) | PCONFIG (101),(11B) | ENCLV (000),(11B) +0: SGDT Ms | VMCALL (001),(11B) | VMLAUNCH (010),(11B) | VMRESUME (011),(11B) | VMXOFF (100),(11B) | PCONFIG (101),(11B) | ENCLV (000),(11B) | WRMSRNS (110),(11B) 1: SIDT Ms | MONITOR (000),(11B) | MWAIT (001),(11B) | CLAC (010),(11B) | STAC (011),(11B) | ENCLS (111),(11B) 2: LGDT Ms | XGETBV (000),(11B) | XSETBV (001),(11B) | VMFUNC (100),(11B) | XEND (101)(11B) | XTEST (110)(11B) | ENCLU (111),(11B) 3: LIDT Ms From patchwork Tue Oct 3 06:24:24 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Li, Xin3" X-Patchwork-Id: 13406831 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4C11CE7542F for ; Tue, 3 Oct 2023 06:54:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239181AbjJCGyv (ORCPT ); Tue, 3 Oct 2023 02:54:51 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37584 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230453AbjJCGyl (ORCPT ); Tue, 3 Oct 2023 02:54:41 -0400 Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.126]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7AFD3B8; Mon, 2 Oct 2023 23:54:38 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1696316078; x=1727852078; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=9qsPaAmdkqHl0KD85EKfAfnheAb+UY4gBzEbjksg7Tw=; b=UFaRe0FHUrEJ/lXqJO7hpm4Lc+av8SoUNxbjvr7rzTOleMnU3d/V4YM4 7kP+N2qPGPcj++JMkvGqdWF6UcN1o7Nma+ezOvlo4GeWF4hhVubhhDN2f 1WycxJfAD9eaj3hB0OTDm5qdA75blYtfinDlMEF3cLMLrGbRPcRDIXt/V 0zxUPYTyMujSfDSfPpP+T2QMqtKkRAGIilxzuYS15/LyWzThqpnAJWkou KRfWkNJYEuIsf6paKd0HC05dny8AsKjzZQ/Ahzjr7beKaOfqCLxuOCX7m km724bBNxS2IAeIXnviOGfjna2MhPbnkHFm092B2jNCdf5isBbm53+71l Q==; X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="367857926" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="367857926" Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Oct 2023 23:54:36 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="1081900902" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="1081900902" Received: from unknown (HELO fred..) ([172.25.112.68]) by fmsmga005.fm.intel.com with ESMTP; 02 Oct 2023 23:54:35 -0700 From: Xin Li To: linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-edac@vger.kernel.org, linux-hyperv@vger.kernel.org, kvm@vger.kernel.org, xen-devel@lists.xenproject.org Cc: tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, luto@kernel.org, pbonzini@redhat.com, seanjc@google.com, peterz@infradead.org, jgross@suse.com, ravi.v.shankar@intel.com, mhiramat@kernel.org, andrew.cooper3@citrix.com, jiangshanlai@gmail.com, nik.borisov@suse.com Subject: [PATCH v12 03/37] x86/msr: Add the WRMSRNS instruction support Date: Mon, 2 Oct 2023 23:24:24 -0700 Message-Id: <20231003062458.23552-4-xin3.li@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231003062458.23552-1-xin3.li@intel.com> References: <20231003062458.23552-1-xin3.li@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Add an always inline API __wrmsrns() to embed the WRMSRNS instruction into the code. Tested-by: Shan Kang Signed-off-by: Xin Li --- arch/x86/include/asm/msr.h | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) diff --git a/arch/x86/include/asm/msr.h b/arch/x86/include/asm/msr.h index 65ec1965cd28..c284ff9ebe67 100644 --- a/arch/x86/include/asm/msr.h +++ b/arch/x86/include/asm/msr.h @@ -97,6 +97,19 @@ static __always_inline void __wrmsr(unsigned int msr, u32 low, u32 high) : : "c" (msr), "a"(low), "d" (high) : "memory"); } +/* + * WRMSRNS behaves exactly like WRMSR with the only difference being + * that it is not a serializing instruction by default. + */ +static __always_inline void __wrmsrns(u32 msr, u32 low, u32 high) +{ + /* Instruction opcode for WRMSRNS; supported in binutils >= 2.40. */ + asm volatile("1: .byte 0x0f,0x01,0xc6\n" + "2:\n" + _ASM_EXTABLE_TYPE(1b, 2b, EX_TYPE_WRMSR) + : : "c" (msr), "a"(low), "d" (high)); +} + #define native_rdmsr(msr, val1, val2) \ do { \ u64 __val = __rdmsr((msr)); \ @@ -297,6 +310,11 @@ do { \ #endif /* !CONFIG_PARAVIRT_XXL */ +static __always_inline void wrmsrns(u32 msr, u64 val) +{ + __wrmsrns(msr, val, val >> 32); +} + /* * 64-bit version of wrmsr_safe(): */ From patchwork Tue Oct 3 06:24:25 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Li, Xin3" X-Patchwork-Id: 13406832 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B1C9CE7542C for ; Tue, 3 Oct 2023 06:54:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239201AbjJCGyw (ORCPT ); Tue, 3 Oct 2023 02:54:52 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37600 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230469AbjJCGyl (ORCPT ); Tue, 3 Oct 2023 02:54:41 -0400 Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.126]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A1CB8BD; Mon, 2 Oct 2023 23:54:38 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1696316078; x=1727852078; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=IaxeoNWuhGDXlIm0wMB8nNslGvpF2+LIDATl0KgTQLA=; b=ec4QYHFK1qDLdwGykgsn+IpRBDuEfHgaL/mEVGzp249u8UG7WZWUCKF8 u0SSJIS+s/8ffX+/OumM6wdTa3obUpzB/U9QigXORmy75Bh9LZVMsQBi7 MBPmug/tnm7BYBGFrnAUUuQ7rH85JXdQNhVB3pKtix+G1MyBGobN3CD0e 3YZRgPLQNGGg3hVg8arJyL1kqioy3ZOImOfvQZ1CMsJTcdAifQYkO0kXu Lsnlfi2XKFWBneBjFtgNRfrJeVO+ojSoZlzfa4UU0giV4rzOp+5buVzQQ 9TjHSJ9oWd6VBIhzmO5YsriBlC1GZwePskARDLdV28B8QbN1vITgQ+kBA w==; X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="367857938" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="367857938" Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Oct 2023 23:54:37 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="1081900906" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="1081900906" Received: from unknown (HELO fred..) ([172.25.112.68]) by fmsmga005.fm.intel.com with ESMTP; 02 Oct 2023 23:54:36 -0700 From: Xin Li To: linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-edac@vger.kernel.org, linux-hyperv@vger.kernel.org, kvm@vger.kernel.org, xen-devel@lists.xenproject.org Cc: tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, luto@kernel.org, pbonzini@redhat.com, seanjc@google.com, peterz@infradead.org, jgross@suse.com, ravi.v.shankar@intel.com, mhiramat@kernel.org, andrew.cooper3@citrix.com, jiangshanlai@gmail.com, nik.borisov@suse.com Subject: [PATCH v12 04/37] x86/entry: Remove idtentry_sysvec from entry_{32,64}.S Date: Mon, 2 Oct 2023 23:24:25 -0700 Message-Id: <20231003062458.23552-5-xin3.li@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231003062458.23552-1-xin3.li@intel.com> References: <20231003062458.23552-1-xin3.li@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org idtentry_sysvec is really just DECLARE_IDTENTRY defined in , no need to define it separately. Tested-by: Shan Kang Signed-off-by: Xin Li --- arch/x86/entry/entry_32.S | 4 ---- arch/x86/entry/entry_64.S | 8 -------- arch/x86/include/asm/idtentry.h | 2 +- 3 files changed, 1 insertion(+), 13 deletions(-) diff --git a/arch/x86/entry/entry_32.S b/arch/x86/entry/entry_32.S index 6e6af42e044a..e0f22ad8ff7e 100644 --- a/arch/x86/entry/entry_32.S +++ b/arch/x86/entry/entry_32.S @@ -649,10 +649,6 @@ SYM_CODE_START_LOCAL(asm_\cfunc) SYM_CODE_END(asm_\cfunc) .endm -.macro idtentry_sysvec vector cfunc - idtentry \vector asm_\cfunc \cfunc has_error_code=0 -.endm - /* * Include the defines which emit the idt entries which are shared * shared between 32 and 64 bit and emit the __irqentry_text_* markers diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S index 9b4b512f2a75..aa4214703091 100644 --- a/arch/x86/entry/entry_64.S +++ b/arch/x86/entry/entry_64.S @@ -432,14 +432,6 @@ SYM_CODE_END(\asmsym) idtentry \vector asm_\cfunc \cfunc has_error_code=1 .endm -/* - * System vectors which invoke their handlers directly and are not - * going through the regular common device interrupt handling code. - */ -.macro idtentry_sysvec vector cfunc - idtentry \vector asm_\cfunc \cfunc has_error_code=0 -.endm - /** * idtentry_mce_db - Macro to generate entry stubs for #MC and #DB * @vector: Vector number diff --git a/arch/x86/include/asm/idtentry.h b/arch/x86/include/asm/idtentry.h index 05fd175cec7d..cfca68f6cb84 100644 --- a/arch/x86/include/asm/idtentry.h +++ b/arch/x86/include/asm/idtentry.h @@ -447,7 +447,7 @@ __visible noinstr void func(struct pt_regs *regs, \ /* System vector entries */ #define DECLARE_IDTENTRY_SYSVEC(vector, func) \ - idtentry_sysvec vector func + DECLARE_IDTENTRY(vector, func) #ifdef CONFIG_X86_64 # define DECLARE_IDTENTRY_MCE(vector, func) \ From patchwork Tue Oct 3 06:24:26 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Li, Xin3" X-Patchwork-Id: 13406833 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9263EE75433 for ; Tue, 3 Oct 2023 06:54:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239195AbjJCGyx (ORCPT ); Tue, 3 Oct 2023 02:54:53 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37606 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230493AbjJCGym (ORCPT ); Tue, 3 Oct 2023 02:54:42 -0400 Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.126]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 59DCDC6; Mon, 2 Oct 2023 23:54:39 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1696316079; x=1727852079; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=peVjyb58aU5czBXdVg55hBuRdCD6fg7woOPGVcAZ2Yw=; b=UIULJJQxydyE0KknC/tregLv6MahhMflEfNPytigX72Ak6iTQ35hTjVv 0sFyl5WT5YPGfAdBpJC10bsVlFNRfFH3jFx+aPtgOz8wlH76HEk5W3n8F kHo6b96uUmU93o3MamB2VabG8y4aAG6+2DpPfb0UV8bSqEXdp3vNsEerx 4M9bYdpXHB+2Ziy7/tSd89yFfTu9AISBSbCc5OJ2MOPyrR4oQH2yaSN02 Oav/SXZB+DN0FT2QQ30vHUgAvrqV6yFcqD68OC/3I1rs37+x+IoXvJbzW NJAtIY0X6F39FjZlv7ebeIzLNLNDFYSp/FDXobkTgpoVKdqG8oLf6mVtB A==; X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="367857954" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="367857954" Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Oct 2023 23:54:37 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="1081900910" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="1081900910" Received: from unknown (HELO fred..) ([172.25.112.68]) by fmsmga005.fm.intel.com with ESMTP; 02 Oct 2023 23:54:36 -0700 From: Xin Li To: linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-edac@vger.kernel.org, linux-hyperv@vger.kernel.org, kvm@vger.kernel.org, xen-devel@lists.xenproject.org Cc: tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, luto@kernel.org, pbonzini@redhat.com, seanjc@google.com, peterz@infradead.org, jgross@suse.com, ravi.v.shankar@intel.com, mhiramat@kernel.org, andrew.cooper3@citrix.com, jiangshanlai@gmail.com, nik.borisov@suse.com Subject: [PATCH v12 05/37] x86/trapnr: Add event type macros to Date: Mon, 2 Oct 2023 23:24:26 -0700 Message-Id: <20231003062458.23552-6-xin3.li@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231003062458.23552-1-xin3.li@intel.com> References: <20231003062458.23552-1-xin3.li@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Intel VT-x classifies events into eight different types, which is inherited by FRED for event identification. As such, event type becomes a common x86 concept, and should be defined in a common x86 header. Add event type macros to , and use it in . Suggested-by: H. Peter Anvin (Intel) Tested-by: Shan Kang Signed-off-by: Xin Li --- Changes since v10: * A few comment fixes and improvements (Andrew Cooper). --- arch/x86/include/asm/trapnr.h | 12 ++++++++++++ arch/x86/include/asm/vmx.h | 17 +++++++++-------- 2 files changed, 21 insertions(+), 8 deletions(-) diff --git a/arch/x86/include/asm/trapnr.h b/arch/x86/include/asm/trapnr.h index f5d2325aa0b7..8d1154cdf787 100644 --- a/arch/x86/include/asm/trapnr.h +++ b/arch/x86/include/asm/trapnr.h @@ -2,6 +2,18 @@ #ifndef _ASM_X86_TRAPNR_H #define _ASM_X86_TRAPNR_H +/* + * Event type codes used by FRED, Intel VT-x and AMD SVM + */ +#define EVENT_TYPE_EXTINT 0 // External interrupt +#define EVENT_TYPE_RESERVED 1 +#define EVENT_TYPE_NMI 2 // NMI +#define EVENT_TYPE_HWEXC 3 // Hardware originated traps, exceptions +#define EVENT_TYPE_SWINT 4 // INT n +#define EVENT_TYPE_PRIV_SWEXC 5 // INT1 +#define EVENT_TYPE_SWEXC 6 // INTO, INT3 +#define EVENT_TYPE_OTHER 7 // FRED SYSCALL/SYSENTER, VT-x MTF + /* Interrupts/Exceptions */ #define X86_TRAP_DE 0 /* Divide-by-zero */ diff --git a/arch/x86/include/asm/vmx.h b/arch/x86/include/asm/vmx.h index 0e73616b82f3..4dba17363008 100644 --- a/arch/x86/include/asm/vmx.h +++ b/arch/x86/include/asm/vmx.h @@ -17,6 +17,7 @@ #include #include +#include #include #define VMCS_CONTROL_BIT(x) BIT(VMX_FEATURE_##x & 0x1f) @@ -374,14 +375,14 @@ enum vmcs_field { #define VECTORING_INFO_DELIVER_CODE_MASK INTR_INFO_DELIVER_CODE_MASK #define VECTORING_INFO_VALID_MASK INTR_INFO_VALID_MASK -#define INTR_TYPE_EXT_INTR (0 << 8) /* external interrupt */ -#define INTR_TYPE_RESERVED (1 << 8) /* reserved */ -#define INTR_TYPE_NMI_INTR (2 << 8) /* NMI */ -#define INTR_TYPE_HARD_EXCEPTION (3 << 8) /* processor exception */ -#define INTR_TYPE_SOFT_INTR (4 << 8) /* software interrupt */ -#define INTR_TYPE_PRIV_SW_EXCEPTION (5 << 8) /* ICE breakpoint - undocumented */ -#define INTR_TYPE_SOFT_EXCEPTION (6 << 8) /* software exception */ -#define INTR_TYPE_OTHER_EVENT (7 << 8) /* other event */ +#define INTR_TYPE_EXT_INTR (EVENT_TYPE_EXTINT << 8) /* external interrupt */ +#define INTR_TYPE_RESERVED (EVENT_TYPE_RESERVED << 8) /* reserved */ +#define INTR_TYPE_NMI_INTR (EVENT_TYPE_NMI << 8) /* NMI */ +#define INTR_TYPE_HARD_EXCEPTION (EVENT_TYPE_HWEXC << 8) /* processor exception */ +#define INTR_TYPE_SOFT_INTR (EVENT_TYPE_SWINT << 8) /* software interrupt */ +#define INTR_TYPE_PRIV_SW_EXCEPTION (EVENT_TYPE_PRIV_SWEXC << 8) /* ICE breakpoint */ +#define INTR_TYPE_SOFT_EXCEPTION (EVENT_TYPE_SWEXC << 8) /* software exception */ +#define INTR_TYPE_OTHER_EVENT (EVENT_TYPE_OTHER << 8) /* other event */ /* GUEST_INTERRUPTIBILITY_INFO flags. */ #define GUEST_INTR_STATE_STI 0x00000001 From patchwork Tue Oct 3 06:24:27 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: "Li, Xin3" X-Patchwork-Id: 13406848 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7AF16E7542F for ; Tue, 3 Oct 2023 06:55:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239261AbjJCGzc (ORCPT ); Tue, 3 Oct 2023 02:55:32 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37608 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230489AbjJCGym (ORCPT ); Tue, 3 Oct 2023 02:54:42 -0400 Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.126]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5ABBEC9; Mon, 2 Oct 2023 23:54:39 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1696316079; x=1727852079; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=bNeoh4I4zABONAQfik1sKjrzvYgDVMEQH0uLYFn+NlU=; b=Fl5TRe3YL11uObDKbfLkP2mt/5i2YIEaGreAl6IBSlmsMIan5ZC9zjAO fXl8syG7hpGXF6H/UTPIc8hD+c8D+sbLmsLTMM2zcHgYrTZUgncurjafO 1xylOQejLNVo+uI47HCXdhkRjaft/8wNFybu/eVjnl7YOJXUxrqYjtNFC IG+JPfNIeyOv+tqhJSqO5qBj0UIL78WgEK4qG0xs1hZEwk22TYY1OHzlo G/qzm7eaVTz8aHsrXWZoyF8DGXsab06sBqMqNMHip9tcSAs8TWv8/9uac cH2x70ISvQMOdTHOlGCJcYUL53W0aqBqhEgrzWGmAILulOdN8uXQJX828 A==; X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="367857966" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="367857966" Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Oct 2023 23:54:38 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="1081900913" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="1081900913" Received: from unknown (HELO fred..) ([172.25.112.68]) by fmsmga005.fm.intel.com with ESMTP; 02 Oct 2023 23:54:37 -0700 From: Xin Li To: linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-edac@vger.kernel.org, linux-hyperv@vger.kernel.org, kvm@vger.kernel.org, xen-devel@lists.xenproject.org Cc: tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, luto@kernel.org, pbonzini@redhat.com, seanjc@google.com, peterz@infradead.org, jgross@suse.com, ravi.v.shankar@intel.com, mhiramat@kernel.org, andrew.cooper3@citrix.com, jiangshanlai@gmail.com, nik.borisov@suse.com Subject: [PATCH v12 06/37] Documentation/x86/64: Add a documentation for FRED Date: Mon, 2 Oct 2023 23:24:27 -0700 Message-Id: <20231003062458.23552-7-xin3.li@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231003062458.23552-1-xin3.li@intel.com> References: <20231003062458.23552-1-xin3.li@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Briefly introduce FRED, and its advantages compared to IDT. Signed-off-by: Xin Li Reviewed-by: Bagas Sanjaya --- Changes since v10: * Reword a sentence to improve readability (Nikolay Borisov). --- Documentation/arch/x86/x86_64/fred.rst | 96 +++++++++++++++++++++++++ Documentation/arch/x86/x86_64/index.rst | 1 + 2 files changed, 97 insertions(+) create mode 100644 Documentation/arch/x86/x86_64/fred.rst diff --git a/Documentation/arch/x86/x86_64/fred.rst b/Documentation/arch/x86/x86_64/fred.rst new file mode 100644 index 000000000000..9f57e7b91f7e --- /dev/null +++ b/Documentation/arch/x86/x86_64/fred.rst @@ -0,0 +1,96 @@ +.. SPDX-License-Identifier: GPL-2.0 + +========================================= +Flexible Return and Event Delivery (FRED) +========================================= + +Overview +======== + +The FRED architecture defines simple new transitions that change +privilege level (ring transitions). The FRED architecture was +designed with the following goals: + +1) Improve overall performance and response time by replacing event + delivery through the interrupt descriptor table (IDT event + delivery) and event return by the IRET instruction with lower + latency transitions. + +2) Improve software robustness by ensuring that event delivery + establishes the full supervisor context and that event return + establishes the full user context. + +The new transitions defined by the FRED architecture are FRED event +delivery and, for returning from events, two FRED return instructions. +FRED event delivery can effect a transition from ring 3 to ring 0, but +it is used also to deliver events incident to ring 0. One FRED +instruction (ERETU) effects a return from ring 0 to ring 3, while the +other (ERETS) returns while remaining in ring 0. Collectively, FRED +event delivery and the FRED return instructions are FRED transitions. + +In addition to these transitions, the FRED architecture defines a new +instruction (LKGS) for managing the state of the GS segment register. +The LKGS instruction can be used by 64-bit operating systems that do +not use the new FRED transitions. + +Furthermore, the FRED architecture is easy to extend for future CPU +architectures. + +Software based event dispatching +================================ + +FRED operates differently from IDT in terms of event handling. Instead +of directly dispatching an event to its handler based on the event +vector, FRED requires the software to dispatch an event to its handler +based on both the event's type and vector. Therefore, an event dispatch +framework must be implemented to facilitate the event-to-handler +dispatch process. The FRED event dispatch framework takes control +once an event is delivered, and employs a two-level dispatch. + +The first level dispatching is event type based, and the second level +dispatching is event vector based. + +Full supervisor/user context +============================ + +FRED event delivery atomically save and restore full supervisor/user +context upon event delivery and return. Thus it avoids the problem of +transient states due to %cr2 and/or %dr6, and it is no longer needed +to handle all the ugly corner cases caused by half baked entry states. + +FRED allows explicit unblock of NMI with new event return instructions +ERETS/ERETU, avoiding the mess caused by IRET which unconditionally +unblocks NMI, e.g., when an exception happens during NMI handling. + +FRED always restores the full value of %rsp, thus ESPFIX is no longer +needed when FRED is enabled. + +LKGS +==== + +LKGS behaves like the MOV to GS instruction except that it loads the +base address into the IA32_KERNEL_GS_BASE MSR instead of the GS +segment’s descriptor cache. With LKGS, it ends up with avoiding +mucking with kernel GS, i.e., an operating system can always operate +with its own GS base address. + +Because FRED event delivery from ring 3 and ERETU both swap the value +of the GS base address and that of the IA32_KERNEL_GS_BASE MSR, plus +the introduction of LKGS instruction, the SWAPGS instruction is no +longer needed when FRED is enabled, thus is disallowed (#UD). + +Stack levels +============ + +4 stack levels 0~3 are introduced to replace the nonreentrant IST for +event handling, and each stack level should be configured to use a +dedicated stack. + +The current stack level could be unchanged or go higher upon FRED +event delivery. If unchanged, the CPU keeps using the current event +stack. If higher, the CPU switches to a new event stack specified by +the MSR of the new stack level, i.e., MSR_IA32_FRED_RSP[123]. + +Only execution of a FRED return instruction ERET[US], could lower the +current stack level, causing the CPU to switch back to the stack it was +on before a previous event delivery that promoted the stack level. diff --git a/Documentation/arch/x86/x86_64/index.rst b/Documentation/arch/x86/x86_64/index.rst index a56070fc8e77..ad15e9bd623f 100644 --- a/Documentation/arch/x86/x86_64/index.rst +++ b/Documentation/arch/x86/x86_64/index.rst @@ -15,3 +15,4 @@ x86_64 Support cpu-hotplug-spec machinecheck fsgs + fred From patchwork Tue Oct 3 06:24:28 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Li, Xin3" X-Patchwork-Id: 13406842 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id C3371E75432 for ; Tue, 3 Oct 2023 06:55:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239331AbjJCGzV (ORCPT ); Tue, 3 Oct 2023 02:55:21 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49940 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239155AbjJCGyt (ORCPT ); Tue, 3 Oct 2023 02:54:49 -0400 Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.126]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 13473CC; Mon, 2 Oct 2023 23:54:40 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1696316080; x=1727852080; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=Z2I9XuVKzLs7Gkjt7VvwoncwktLr23Bll2CpTX5dzXE=; b=jj8jn6NLWISoGg9tlcdry69aCf4bXOncovk15oc39cK88nM0DjAt/wAt GmP6IqapgBtcXIRRrue3oLcDq7eXROfSG4ImWNnFbLGmElY6lNBNIcMU2 lzGRtEIwyxOtkc6BQ/z26BZUh91TNuzldMoP1fFYA/5Eemq8kSMLhTGBM 48ecJngS2R1wG5e5+zvthqg8sQ88SxrrkliwAUGAV9XxuPBzTOd7b/mlo Kzzv7kASOq56mu4CR/3IC63jLfCRv1ljVJJFU9YW+URsMRuSY1WPIT/s9 OylOTVQwwdcAdRNOxSD9i708ws+O60SmFPpaher0f3L01Hn7bX6oH5fY1 g==; X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="367857978" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="367857978" Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Oct 2023 23:54:38 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="1081900916" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="1081900916" Received: from unknown (HELO fred..) ([172.25.112.68]) by fmsmga005.fm.intel.com with ESMTP; 02 Oct 2023 23:54:37 -0700 From: Xin Li To: linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-edac@vger.kernel.org, linux-hyperv@vger.kernel.org, kvm@vger.kernel.org, xen-devel@lists.xenproject.org Cc: tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, luto@kernel.org, pbonzini@redhat.com, seanjc@google.com, peterz@infradead.org, jgross@suse.com, ravi.v.shankar@intel.com, mhiramat@kernel.org, andrew.cooper3@citrix.com, jiangshanlai@gmail.com, nik.borisov@suse.com Subject: [PATCH v12 07/37] x86/fred: Add Kconfig option for FRED (CONFIG_X86_FRED) Date: Mon, 2 Oct 2023 23:24:28 -0700 Message-Id: <20231003062458.23552-8-xin3.li@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231003062458.23552-1-xin3.li@intel.com> References: <20231003062458.23552-1-xin3.li@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: "H. Peter Anvin (Intel)" Add the configuration option CONFIG_X86_FRED to enable FRED. Signed-off-by: H. Peter Anvin (Intel) Tested-by: Shan Kang Signed-off-by: Xin Li --- arch/x86/Kconfig | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 433f5e1906d1..5ef2f6fe0681 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -496,6 +496,15 @@ config X86_CPU_RESCTRL Say N if unsure. +config X86_FRED + bool "Flexible Return and Event Delivery" + depends on X86_64 + help + When enabled, try to use Flexible Return and Event Delivery + instead of the legacy SYSCALL/SYSENTER/IDT architecture for + ring transitions and exception/interrupt handling if the + system supports. + if X86_32 config X86_BIGSMP bool "Support for big SMP systems with more than 8 CPUs" From patchwork Tue Oct 3 06:24:29 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: "Li, Xin3" X-Patchwork-Id: 13406846 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8422CE7542E for ; Tue, 3 Oct 2023 06:55:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239211AbjJCGz3 (ORCPT ); Tue, 3 Oct 2023 02:55:29 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37614 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231143AbjJCGyp (ORCPT ); Tue, 3 Oct 2023 02:54:45 -0400 Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.126]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CE044AC; Mon, 2 Oct 2023 23:54:40 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1696316080; x=1727852080; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=ZlGESG1ZjbxHp/2vGEpu7uzY2F9a0taEPQgxug8c1Qc=; b=DdNTFRnWCD5x4zUxqLXw5z9MBxr2tps6yuWMIBsu03/Ms/tyQRlgRoJ5 aaCGhKXb4c0tU5qXeWBo3+aGh8GMOzwNS9zLpOdT50MRIi6a6EL+7eZfS hEdYLA9UETFIzrQNJNjpXVRInz1Qi8F7nUgqUFcBTSd6zpmQfD8/XZtXP umbnR2CYS0SgcHASJVlHOAKu6E3gUWWXhOlZX8mz0sIqJQgHNwWvb6dcE XmBMAYVlqIhBONigdL0UI3NaMVn4XDEa0eqmbAMVkpTTTfMCeXyggLmB3 jNv3JcjeqBHOnCumc0WDBueaQa367rS4wUHcjBTBCDB9AuyQNKurSXmcG g==; X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="367857991" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="367857991" Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Oct 2023 23:54:39 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="1081900919" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="1081900919" Received: from unknown (HELO fred..) ([172.25.112.68]) by fmsmga005.fm.intel.com with ESMTP; 02 Oct 2023 23:54:38 -0700 From: Xin Li To: linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-edac@vger.kernel.org, linux-hyperv@vger.kernel.org, kvm@vger.kernel.org, xen-devel@lists.xenproject.org Cc: tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, luto@kernel.org, pbonzini@redhat.com, seanjc@google.com, peterz@infradead.org, jgross@suse.com, ravi.v.shankar@intel.com, mhiramat@kernel.org, andrew.cooper3@citrix.com, jiangshanlai@gmail.com, nik.borisov@suse.com Subject: [PATCH v12 08/37] x86/cpufeatures: Add the cpu feature bit for FRED Date: Mon, 2 Oct 2023 23:24:29 -0700 Message-Id: <20231003062458.23552-9-xin3.li@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231003062458.23552-1-xin3.li@intel.com> References: <20231003062458.23552-1-xin3.li@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: "H. Peter Anvin (Intel)" Any FRED CPU will always have the following features as its baseline: 1) LKGS, load attributes of the GS segment but the base address into the IA32_KERNEL_GS_BASE MSR instead of the GS segment’s descriptor cache. 2) WRMSRNS, non-serializing WRMSR for faster MSR writes. Signed-off-by: H. Peter Anvin (Intel) Tested-by: Shan Kang Signed-off-by: Xin Li --- arch/x86/include/asm/cpufeatures.h | 1 + arch/x86/kernel/cpu/cpuid-deps.c | 2 ++ tools/arch/x86/include/asm/cpufeatures.h | 1 + 3 files changed, 4 insertions(+) diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h index 330876d34b68..57ae93dc1e52 100644 --- a/arch/x86/include/asm/cpufeatures.h +++ b/arch/x86/include/asm/cpufeatures.h @@ -321,6 +321,7 @@ #define X86_FEATURE_FZRM (12*32+10) /* "" Fast zero-length REP MOVSB */ #define X86_FEATURE_FSRS (12*32+11) /* "" Fast short REP STOSB */ #define X86_FEATURE_FSRC (12*32+12) /* "" Fast short REP {CMPSB,SCASB} */ +#define X86_FEATURE_FRED (12*32+17) /* Flexible Return and Event Delivery */ #define X86_FEATURE_LKGS (12*32+18) /* "" Load "kernel" (userspace) GS */ #define X86_FEATURE_WRMSRNS (12*32+19) /* "" Non-Serializing Write to Model Specific Register instruction */ #define X86_FEATURE_AMX_FP16 (12*32+21) /* "" AMX fp16 Support */ diff --git a/arch/x86/kernel/cpu/cpuid-deps.c b/arch/x86/kernel/cpu/cpuid-deps.c index e462c1d3800a..b7174209d855 100644 --- a/arch/x86/kernel/cpu/cpuid-deps.c +++ b/arch/x86/kernel/cpu/cpuid-deps.c @@ -82,6 +82,8 @@ static const struct cpuid_dep cpuid_deps[] = { { X86_FEATURE_XFD, X86_FEATURE_XGETBV1 }, { X86_FEATURE_AMX_TILE, X86_FEATURE_XFD }, { X86_FEATURE_SHSTK, X86_FEATURE_XSAVES }, + { X86_FEATURE_FRED, X86_FEATURE_LKGS }, + { X86_FEATURE_FRED, X86_FEATURE_WRMSRNS }, {} }; diff --git a/tools/arch/x86/include/asm/cpufeatures.h b/tools/arch/x86/include/asm/cpufeatures.h index 1b9d86ba5bc2..18bab7987d7f 100644 --- a/tools/arch/x86/include/asm/cpufeatures.h +++ b/tools/arch/x86/include/asm/cpufeatures.h @@ -317,6 +317,7 @@ #define X86_FEATURE_FZRM (12*32+10) /* "" Fast zero-length REP MOVSB */ #define X86_FEATURE_FSRS (12*32+11) /* "" Fast short REP STOSB */ #define X86_FEATURE_FSRC (12*32+12) /* "" Fast short REP {CMPSB,SCASB} */ +#define X86_FEATURE_FRED (12*32+17) /* Flexible Return and Event Delivery */ #define X86_FEATURE_LKGS (12*32+18) /* "" Load "kernel" (userspace) GS */ #define X86_FEATURE_WRMSRNS (12*32+19) /* "" Non-Serializing Write to Model Specific Register instruction */ #define X86_FEATURE_AMX_FP16 (12*32+21) /* "" AMX fp16 Support */ From patchwork Tue Oct 3 06:24:30 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Li, Xin3" X-Patchwork-Id: 13406847 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8178BE75428 for ; Tue, 3 Oct 2023 06:55:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239391AbjJCGza (ORCPT ); Tue, 3 Oct 2023 02:55:30 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37616 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231140AbjJCGyp (ORCPT ); Tue, 3 Oct 2023 02:54:45 -0400 Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.126]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D634CAD; Mon, 2 Oct 2023 23:54:40 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1696316080; x=1727852080; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=CcGvpPsp9yPYBKGgtw+pwzSruaWdmcjQipAacX3tyYo=; b=EAFkT0UKoflFr+of1b8fKClDC2Tgb82DsxObPOi2muItg/G2EngsV5Lu oU3VZ5hTZly6aT5bAD0DDZ4nVhRDFOJJR3Da1yOdKiV0ruKotbXOWLxEa kIY4Ec2/4hEe35mnDGjUkh+idE32V1kwgK6gtjCGhUXXV8A4yi7mZa0yz pTrDLjVfScFgRe3TsXGk8vDWaEIQ+ZyGmP+yBfgy2ttkpPJV6OkZkiYbp 3mcVry5mbrriHzSXa9tEPuw1Vz/qBueb3rNfKjvy84V3Flv8jehd2oXB8 27BVx1ZnaBeWfE9enDaQhqXgqpP490d27qCMfeMxvSC7MrY0aat5SqwIb A==; X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="367858003" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="367858003" Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Oct 2023 23:54:39 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="1081900922" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="1081900922" Received: from unknown (HELO fred..) ([172.25.112.68]) by fmsmga005.fm.intel.com with ESMTP; 02 Oct 2023 23:54:38 -0700 From: Xin Li To: linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-edac@vger.kernel.org, linux-hyperv@vger.kernel.org, kvm@vger.kernel.org, xen-devel@lists.xenproject.org Cc: tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, luto@kernel.org, pbonzini@redhat.com, seanjc@google.com, peterz@infradead.org, jgross@suse.com, ravi.v.shankar@intel.com, mhiramat@kernel.org, andrew.cooper3@citrix.com, jiangshanlai@gmail.com, nik.borisov@suse.com Subject: [PATCH v12 09/37] x86/fred: Disable FRED support if CONFIG_X86_FRED is disabled Date: Mon, 2 Oct 2023 23:24:30 -0700 Message-Id: <20231003062458.23552-10-xin3.li@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231003062458.23552-1-xin3.li@intel.com> References: <20231003062458.23552-1-xin3.li@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: "H. Peter Anvin (Intel)" Add CONFIG_X86_FRED to to make cpu_feature_enabled() work correctly with FRED. Originally-by: Megha Dey Signed-off-by: H. Peter Anvin (Intel) Tested-by: Shan Kang Signed-off-by: Xin Li --- Changes since v10: * FRED feature is defined in cpuid word 12, not 13 (Nikolay Borisov). --- arch/x86/include/asm/disabled-features.h | 8 +++++++- tools/arch/x86/include/asm/disabled-features.h | 8 +++++++- 2 files changed, 14 insertions(+), 2 deletions(-) diff --git a/arch/x86/include/asm/disabled-features.h b/arch/x86/include/asm/disabled-features.h index 702d93fdd10e..f40b29d3abad 100644 --- a/arch/x86/include/asm/disabled-features.h +++ b/arch/x86/include/asm/disabled-features.h @@ -117,6 +117,12 @@ #define DISABLE_IBT (1 << (X86_FEATURE_IBT & 31)) #endif +#ifdef CONFIG_X86_FRED +# define DISABLE_FRED 0 +#else +# define DISABLE_FRED (1 << (X86_FEATURE_FRED & 31)) +#endif + /* * Make sure to add features to the correct mask */ @@ -133,7 +139,7 @@ #define DISABLED_MASK10 0 #define DISABLED_MASK11 (DISABLE_RETPOLINE|DISABLE_RETHUNK|DISABLE_UNRET| \ DISABLE_CALL_DEPTH_TRACKING|DISABLE_USER_SHSTK) -#define DISABLED_MASK12 (DISABLE_LAM) +#define DISABLED_MASK12 (DISABLE_FRED|DISABLE_LAM) #define DISABLED_MASK13 0 #define DISABLED_MASK14 0 #define DISABLED_MASK15 0 diff --git a/tools/arch/x86/include/asm/disabled-features.h b/tools/arch/x86/include/asm/disabled-features.h index fafe9be7a6f4..0b47ab1930a3 100644 --- a/tools/arch/x86/include/asm/disabled-features.h +++ b/tools/arch/x86/include/asm/disabled-features.h @@ -105,6 +105,12 @@ # define DISABLE_TDX_GUEST (1 << (X86_FEATURE_TDX_GUEST & 31)) #endif +#ifdef CONFIG_X86_FRED +# define DISABLE_FRED 0 +#else +# define DISABLE_FRED (1 << (X86_FEATURE_FRED & 31)) +#endif + /* * Make sure to add features to the correct mask */ @@ -121,7 +127,7 @@ #define DISABLED_MASK10 0 #define DISABLED_MASK11 (DISABLE_RETPOLINE|DISABLE_RETHUNK|DISABLE_UNRET| \ DISABLE_CALL_DEPTH_TRACKING) -#define DISABLED_MASK12 (DISABLE_LAM) +#define DISABLED_MASK12 (DISABLE_FRED|DISABLE_LAM) #define DISABLED_MASK13 0 #define DISABLED_MASK14 0 #define DISABLED_MASK15 0 From patchwork Tue Oct 3 06:24:31 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Li, Xin3" X-Patchwork-Id: 13406844 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id C1ED0E7542D for ; Tue, 3 Oct 2023 06:55:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239340AbjJCGzX (ORCPT ); Tue, 3 Oct 2023 02:55:23 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37606 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239175AbjJCGyu (ORCPT ); Tue, 3 Oct 2023 02:54:50 -0400 Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.126]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 84354DA; Mon, 2 Oct 2023 23:54:43 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1696316083; x=1727852083; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=aQdiRWsnt6AKxUkiRSvWlc5kg1W+wRYx8vYlgG3sGOg=; b=HAnkFzOLjW/W+y3rwOp9u/XEe/TbgKJey2/vNwyJBRBxkrG+ZnRlLMj5 8DayFkXleC0xGUNGtbzF90IbxWtam5YpUG0518Q2mg3RGk6IjldAN9XVS vvYB/2l2EdLGFbigzuIlWqvis+VTLvEHknLAAHAc4kWmL+yqeTRi5eht6 Ng2S826YlMvvNgsxNiIVEF93poHoXERtTfn87TOnEk9ZMumWLHkl3TRIY lZKVPrGzW8jHKeNEcS5DX93+dPLkAMuHDrlPbt6KFttH0FQDsg/byHduu x3+ETyAXZ+DDa18RAxS48kQZkLsXysjYd1hFYE/1kJakve2gBxS1yFKUN g==; X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="367858015" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="367858015" Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Oct 2023 23:54:40 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="1081900925" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="1081900925" Received: from unknown (HELO fred..) ([172.25.112.68]) by fmsmga005.fm.intel.com with ESMTP; 02 Oct 2023 23:54:39 -0700 From: Xin Li To: linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-edac@vger.kernel.org, linux-hyperv@vger.kernel.org, kvm@vger.kernel.org, xen-devel@lists.xenproject.org Cc: tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, luto@kernel.org, pbonzini@redhat.com, seanjc@google.com, peterz@infradead.org, jgross@suse.com, ravi.v.shankar@intel.com, mhiramat@kernel.org, andrew.cooper3@citrix.com, jiangshanlai@gmail.com, nik.borisov@suse.com Subject: [PATCH v12 10/37] x86/fred: Disable FRED by default in its early stage Date: Mon, 2 Oct 2023 23:24:31 -0700 Message-Id: <20231003062458.23552-11-xin3.li@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231003062458.23552-1-xin3.li@intel.com> References: <20231003062458.23552-1-xin3.li@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org To enable FRED, a new kernel command line option "fred" needs to be added. Tested-by: Shan Kang Signed-off-by: Xin Li --- Documentation/admin-guide/kernel-parameters.txt | 3 +++ arch/x86/kernel/cpu/common.c | 3 +++ 2 files changed, 6 insertions(+) diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 45e34be4ed56..ee939ea00458 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -1525,6 +1525,9 @@ Warning: use of this parameter will taint the kernel and may cause unknown problems. + fred [X86-64] + Enable flexible return and event delivery + ftrace=[tracer] [FTRACE] will set and start the specified tracer as early as possible in order to facilitate early diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index 7131074433f9..736d38abfc5a 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -1502,6 +1502,9 @@ static void __init cpu_parse_early_param(void) char *argptr = arg, *opt; int arglen, taint = 0; + if (!cmdline_find_option_bool(boot_command_line, "fred")) + setup_clear_cpu_cap(X86_FEATURE_FRED); + #ifdef CONFIG_X86_32 if (cmdline_find_option_bool(boot_command_line, "no387")) #ifdef CONFIG_MATH_EMULATION From patchwork Tue Oct 3 06:24:32 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Li, Xin3" X-Patchwork-Id: 13406834 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A3229E7542C for ; Tue, 3 Oct 2023 06:54:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239255AbjJCGyz (ORCPT ); Tue, 3 Oct 2023 02:54:55 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37608 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239184AbjJCGyv (ORCPT ); Tue, 3 Oct 2023 02:54:51 -0400 Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.126]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B51F3DD; Mon, 2 Oct 2023 23:54:43 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1696316083; x=1727852083; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=i5VPM7WJy8QX3AfDJPn+y86GzsjxiQoeNBcvUeRwUoQ=; b=OwLVC44mlD5Q1qhL+d8Y/7ROid0I25+bOxRoDRoYqNLWsX4i5CWCn9ML /2mkwuBYUSH6TxanccwTrKcCNLJ6f1mysaaIQP7CPO376WixYASU0uUvX 7/4sFzuliY1d332HHpgRYSvwVPq3DayKfMvg5U3J8m+F0J7leENrUs8zJ I66xV4eIreZ+MLntiGc84ehOTmWvvqYSG+FMy7D75NqDBWt8GSp6aPmPW jynoYsf7Z4fD6vJanSCqwEd0DNGrz4xmADBVFFwo3ESsjEqZx2eiwDFYN ybxt/wQG3vX1Lv1psarS/D+OsTwVm+cdwEr4AjsSvWVGt/qtGLTwVLabs g==; X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="367858027" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="367858027" Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Oct 2023 23:54:40 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="1081900928" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="1081900928" Received: from unknown (HELO fred..) ([172.25.112.68]) by fmsmga005.fm.intel.com with ESMTP; 02 Oct 2023 23:54:40 -0700 From: Xin Li To: linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-edac@vger.kernel.org, linux-hyperv@vger.kernel.org, kvm@vger.kernel.org, xen-devel@lists.xenproject.org Cc: tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, luto@kernel.org, pbonzini@redhat.com, seanjc@google.com, peterz@infradead.org, jgross@suse.com, ravi.v.shankar@intel.com, mhiramat@kernel.org, andrew.cooper3@citrix.com, jiangshanlai@gmail.com, nik.borisov@suse.com Subject: [PATCH v12 11/37] x86/opcode: Add ERET[US] instructions to the x86 opcode map Date: Mon, 2 Oct 2023 23:24:32 -0700 Message-Id: <20231003062458.23552-12-xin3.li@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231003062458.23552-1-xin3.li@intel.com> References: <20231003062458.23552-1-xin3.li@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: "H. Peter Anvin (Intel)" ERETU returns from an event handler while making a transition to ring 3, and ERETS returns from an event handler while staying in ring 0. Add instruction opcodes used by ERET[US] to the x86 opcode map; opcode numbers are per FRED spec v5.0. Signed-off-by: H. Peter Anvin (Intel) Tested-by: Shan Kang Signed-off-by: Xin Li Reviewed-by: Masami Hiramatsu (Google) --- arch/x86/lib/x86-opcode-map.txt | 2 +- tools/arch/x86/lib/x86-opcode-map.txt | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/x86/lib/x86-opcode-map.txt b/arch/x86/lib/x86-opcode-map.txt index 1efe1d9bf5ce..12af572201a2 100644 --- a/arch/x86/lib/x86-opcode-map.txt +++ b/arch/x86/lib/x86-opcode-map.txt @@ -1052,7 +1052,7 @@ EndTable GrpTable: Grp7 0: SGDT Ms | VMCALL (001),(11B) | VMLAUNCH (010),(11B) | VMRESUME (011),(11B) | VMXOFF (100),(11B) | PCONFIG (101),(11B) | ENCLV (000),(11B) | WRMSRNS (110),(11B) -1: SIDT Ms | MONITOR (000),(11B) | MWAIT (001),(11B) | CLAC (010),(11B) | STAC (011),(11B) | ENCLS (111),(11B) +1: SIDT Ms | MONITOR (000),(11B) | MWAIT (001),(11B) | CLAC (010),(11B) | STAC (011),(11B) | ENCLS (111),(11B) | ERETU (F3),(010),(11B) | ERETS (F2),(010),(11B) 2: LGDT Ms | XGETBV (000),(11B) | XSETBV (001),(11B) | VMFUNC (100),(11B) | XEND (101)(11B) | XTEST (110)(11B) | ENCLU (111),(11B) 3: LIDT Ms 4: SMSW Mw/Rv diff --git a/tools/arch/x86/lib/x86-opcode-map.txt b/tools/arch/x86/lib/x86-opcode-map.txt index 1efe1d9bf5ce..12af572201a2 100644 --- a/tools/arch/x86/lib/x86-opcode-map.txt +++ b/tools/arch/x86/lib/x86-opcode-map.txt @@ -1052,7 +1052,7 @@ EndTable GrpTable: Grp7 0: SGDT Ms | VMCALL (001),(11B) | VMLAUNCH (010),(11B) | VMRESUME (011),(11B) | VMXOFF (100),(11B) | PCONFIG (101),(11B) | ENCLV (000),(11B) | WRMSRNS (110),(11B) -1: SIDT Ms | MONITOR (000),(11B) | MWAIT (001),(11B) | CLAC (010),(11B) | STAC (011),(11B) | ENCLS (111),(11B) +1: SIDT Ms | MONITOR (000),(11B) | MWAIT (001),(11B) | CLAC (010),(11B) | STAC (011),(11B) | ENCLS (111),(11B) | ERETU (F3),(010),(11B) | ERETS (F2),(010),(11B) 2: LGDT Ms | XGETBV (000),(11B) | XSETBV (001),(11B) | VMFUNC (100),(11B) | XEND (101)(11B) | XTEST (110)(11B) | ENCLU (111),(11B) 3: LIDT Ms 4: SMSW Mw/Rv From patchwork Tue Oct 3 06:24:33 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Li, Xin3" X-Patchwork-Id: 13406845 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9967AE7542C for ; Tue, 3 Oct 2023 06:55:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239353AbjJCGz0 (ORCPT ); Tue, 3 Oct 2023 02:55:26 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37600 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239156AbjJCGyt (ORCPT ); Tue, 3 Oct 2023 02:54:49 -0400 Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.126]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B5263E0; Mon, 2 Oct 2023 23:54:43 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1696316083; x=1727852083; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=nnaiSfOR32UqURagnGQyKATdoHKyxN7QZzCa/h9+/jY=; b=mYQJghx5+ZYjU99/6b9cpAIhI0Tl1nLjZX+DvnvVmRCeSjQiM46n61mW ZtMAww0b1iCTbl77/f0GrDod8pW0K7TeU82cIZFaHraSAt8Sg+BQJaX/r pBiiAck3vQ99pHtvApiT/qccBB/oi30R/LHtG/BlbR29GdZASkIhSN+Q5 Qj6AMrDuGWuk89PN4GdHBzZYSnpXYNXGY4d9I+X7kXlS2LUlU7Y39YSpU qrMxWdFM0wAGC14ReXwoDJIc5h8OCwzRGrz2yuHU48C6uErBQbpHUjg7+ T1UH4WZqgolVCLZicYfxLlLYfyHUyRJAGcSraUvtJqp6PuDGXUV/7Ot42 Q==; X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="367858039" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="367858039" Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Oct 2023 23:54:41 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="1081900931" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="1081900931" Received: from unknown (HELO fred..) ([172.25.112.68]) by fmsmga005.fm.intel.com with ESMTP; 02 Oct 2023 23:54:40 -0700 From: Xin Li To: linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-edac@vger.kernel.org, linux-hyperv@vger.kernel.org, kvm@vger.kernel.org, xen-devel@lists.xenproject.org Cc: tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, luto@kernel.org, pbonzini@redhat.com, seanjc@google.com, peterz@infradead.org, jgross@suse.com, ravi.v.shankar@intel.com, mhiramat@kernel.org, andrew.cooper3@citrix.com, jiangshanlai@gmail.com, nik.borisov@suse.com Subject: [PATCH v12 12/37] x86/objtool: Teach objtool about ERET[US] Date: Mon, 2 Oct 2023 23:24:33 -0700 Message-Id: <20231003062458.23552-13-xin3.li@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231003062458.23552-1-xin3.li@intel.com> References: <20231003062458.23552-1-xin3.li@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: "H. Peter Anvin (Intel)" Update the objtool decoder to know about the ERET[US] instructions (type INSN_CONTEXT_SWITCH). Signed-off-by: H. Peter Anvin (Intel) Tested-by: Shan Kang Signed-off-by: Xin Li --- tools/objtool/arch/x86/decode.c | 19 ++++++++++++++----- 1 file changed, 14 insertions(+), 5 deletions(-) diff --git a/tools/objtool/arch/x86/decode.c b/tools/objtool/arch/x86/decode.c index c0f25d00181e..6999f478c155 100644 --- a/tools/objtool/arch/x86/decode.c +++ b/tools/objtool/arch/x86/decode.c @@ -509,11 +509,20 @@ int arch_decode_instruction(struct objtool_file *file, const struct section *sec if (op2 == 0x01) { - if (modrm == 0xca) - insn->type = INSN_CLAC; - else if (modrm == 0xcb) - insn->type = INSN_STAC; - + switch (insn_last_prefix_id(&ins)) { + case INAT_PFX_REPE: + case INAT_PFX_REPNE: + if (modrm == 0xca) + /* eretu/erets */ + insn->type = INSN_CONTEXT_SWITCH; + break; + default: + if (modrm == 0xca) + insn->type = INSN_CLAC; + else if (modrm == 0xcb) + insn->type = INSN_STAC; + break; + } } else if (op2 >= 0x80 && op2 <= 0x8f) { insn->type = INSN_JUMP_CONDITIONAL; From patchwork Tue Oct 3 06:24:34 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Li, Xin3" X-Patchwork-Id: 13406843 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3781BE7542C for ; Tue, 3 Oct 2023 06:55:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239191AbjJCGzT (ORCPT ); Tue, 3 Oct 2023 02:55:19 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49996 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239192AbjJCGyv (ORCPT ); Tue, 3 Oct 2023 02:54:51 -0400 Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.126]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7C5F4F1; Mon, 2 Oct 2023 23:54:45 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1696316085; x=1727852085; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=nFX1zfVQEUHSVWboxtoxLzmp8lIUuta3YE4l1C8KOLQ=; b=lry1aLSZgjI5mmuMnWcSMMiUBpLLSIYmTom5dP7u5SrPYEXZ98lHGwvC gHnWI9sRL8urtSW/LbkyoGx49XOCxymZ1eg2qTZTB1+oxPCkFs91+KFQu URwnK/IGoyOvIaozCPmIqXK61wPb0Cm/0409hNB6tL5EzNcbyZ5yaM1/x DK3Fog85rL8tmsRU/tvu2b2LgHApjbDbxBpFVIzjSDhHn2UafN6+zydb2 er8sRva/MXZBD1Z8RoGhW9yAW9yLL6rVL+WTk24+K5TR4tQZLt9VguE/N te+apl3PqOJEeWFTJsFMxySYhPW+EdY++4qk6SKw2Dm1HEpLgmkpQhOtK A==; X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="367858051" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="367858051" Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Oct 2023 23:54:41 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="1081900934" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="1081900934" Received: from unknown (HELO fred..) ([172.25.112.68]) by fmsmga005.fm.intel.com with ESMTP; 02 Oct 2023 23:54:41 -0700 From: Xin Li To: linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-edac@vger.kernel.org, linux-hyperv@vger.kernel.org, kvm@vger.kernel.org, xen-devel@lists.xenproject.org Cc: tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, luto@kernel.org, pbonzini@redhat.com, seanjc@google.com, peterz@infradead.org, jgross@suse.com, ravi.v.shankar@intel.com, mhiramat@kernel.org, andrew.cooper3@citrix.com, jiangshanlai@gmail.com, nik.borisov@suse.com Subject: [PATCH v12 13/37] x86/cpu: Add X86_CR4_FRED macro Date: Mon, 2 Oct 2023 23:24:34 -0700 Message-Id: <20231003062458.23552-14-xin3.li@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231003062458.23552-1-xin3.li@intel.com> References: <20231003062458.23552-1-xin3.li@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: "H. Peter Anvin (Intel)" Add X86_CR4_FRED macro for the FRED bit in %cr4. This bit must not be changed after initialization, so add it to the pinned CR4 bits. Signed-off-by: H. Peter Anvin (Intel) Tested-by: Shan Kang Signed-off-by: Xin Li --- Changes since v9: * Avoid a type cast by defining X86_CR4_FRED as 0 on 32-bit (Thomas Gleixner). --- arch/x86/include/uapi/asm/processor-flags.h | 7 +++++++ arch/x86/kernel/cpu/common.c | 5 ++--- 2 files changed, 9 insertions(+), 3 deletions(-) diff --git a/arch/x86/include/uapi/asm/processor-flags.h b/arch/x86/include/uapi/asm/processor-flags.h index d898432947ff..f1a4adc78272 100644 --- a/arch/x86/include/uapi/asm/processor-flags.h +++ b/arch/x86/include/uapi/asm/processor-flags.h @@ -139,6 +139,13 @@ #define X86_CR4_LAM_SUP_BIT 28 /* LAM for supervisor pointers */ #define X86_CR4_LAM_SUP _BITUL(X86_CR4_LAM_SUP_BIT) +#ifdef __x86_64__ +#define X86_CR4_FRED_BIT 32 /* enable FRED kernel entry */ +#define X86_CR4_FRED _BITUL(X86_CR4_FRED_BIT) +#else +#define X86_CR4_FRED (0) +#endif + /* * x86-64 Task Priority Register, CR8 */ diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index 736d38abfc5a..9b1cb6c938c4 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -401,9 +401,8 @@ static __always_inline void setup_umip(struct cpuinfo_x86 *c) } /* These bits should not change their value after CPU init is finished. */ -static const unsigned long cr4_pinned_mask = - X86_CR4_SMEP | X86_CR4_SMAP | X86_CR4_UMIP | - X86_CR4_FSGSBASE | X86_CR4_CET; +static const unsigned long cr4_pinned_mask = X86_CR4_SMEP | X86_CR4_SMAP | X86_CR4_UMIP | + X86_CR4_FSGSBASE | X86_CR4_CET | X86_CR4_FRED; static DEFINE_STATIC_KEY_FALSE_RO(cr_pinning); static unsigned long cr4_pinned_bits __ro_after_init; From patchwork Tue Oct 3 06:24:35 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Li, Xin3" X-Patchwork-Id: 13406841 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6C3F3E75438 for ; Tue, 3 Oct 2023 06:55:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239234AbjJCGzS (ORCPT ); Tue, 3 Oct 2023 02:55:18 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49974 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239204AbjJCGyw (ORCPT ); Tue, 3 Oct 2023 02:54:52 -0400 Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.126]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AD3BDF2; Mon, 2 Oct 2023 23:54:45 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1696316085; x=1727852085; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=nTdktbAXAsluEm2oV29DBlIQh6+yrXokZRkKJ/w8Zmc=; b=Us9f8Tj5uCZpSnV/cmOX5Gg5cPnP1yu6wSiJdo5ENspqZ0ORmzC9eosq 7Ffn7PJRi5OXCaHosnowkElRyDLuKJcWM9DIDb3YKN3tT6mQYN5jrMpqf 0UWL7yZGaw8g8fEifHUEpxAdwSteSnyjtKM3d747/rKuMZHv7gQaWYF3X dxLeVzi+zW75TiWcwfG5gOIO2BuBUT4pK8oOh3ewZfBLjTUL3d5sfLDN4 +saxtCCx37uMTwrDHtBOMpRoysQ80WQ91miiQAnGfsLNkbt7mrglgnpwx NG29sErzTiG41cXC/xRS3sCmlFj3aAgyfWCglDGNMXYfDE8HHqYb+MUj6 A==; X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="367858063" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="367858063" Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Oct 2023 23:54:42 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="1081900937" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="1081900937" Received: from unknown (HELO fred..) ([172.25.112.68]) by fmsmga005.fm.intel.com with ESMTP; 02 Oct 2023 23:54:41 -0700 From: Xin Li To: linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-edac@vger.kernel.org, linux-hyperv@vger.kernel.org, kvm@vger.kernel.org, xen-devel@lists.xenproject.org Cc: tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, luto@kernel.org, pbonzini@redhat.com, seanjc@google.com, peterz@infradead.org, jgross@suse.com, ravi.v.shankar@intel.com, mhiramat@kernel.org, andrew.cooper3@citrix.com, jiangshanlai@gmail.com, nik.borisov@suse.com Subject: [PATCH v12 14/37] x86/cpu: Add MSR numbers for FRED configuration Date: Mon, 2 Oct 2023 23:24:35 -0700 Message-Id: <20231003062458.23552-15-xin3.li@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231003062458.23552-1-xin3.li@intel.com> References: <20231003062458.23552-1-xin3.li@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: "H. Peter Anvin (Intel)" Add MSR numbers for the FRED configuration registers per FRED spec 5.0. Originally-by: Megha Dey Signed-off-by: H. Peter Anvin (Intel) Tested-by: Shan Kang Signed-off-by: Xin Li --- arch/x86/include/asm/msr-index.h | 13 ++++++++++++- tools/arch/x86/include/asm/msr-index.h | 13 ++++++++++++- 2 files changed, 24 insertions(+), 2 deletions(-) diff --git a/arch/x86/include/asm/msr-index.h b/arch/x86/include/asm/msr-index.h index 6a6b0f763f67..200d7715696d 100644 --- a/arch/x86/include/asm/msr-index.h +++ b/arch/x86/include/asm/msr-index.h @@ -36,8 +36,19 @@ #define EFER_FFXSR (1<<_EFER_FFXSR) #define EFER_AUTOIBRS (1<<_EFER_AUTOIBRS) -/* Intel MSRs. Some also available on other CPUs */ +/* FRED MSRs */ +#define MSR_IA32_FRED_RSP0 0x1cc /* Level 0 stack pointer */ +#define MSR_IA32_FRED_RSP1 0x1cd /* Level 1 stack pointer */ +#define MSR_IA32_FRED_RSP2 0x1ce /* Level 2 stack pointer */ +#define MSR_IA32_FRED_RSP3 0x1cf /* Level 3 stack pointer */ +#define MSR_IA32_FRED_STKLVLS 0x1d0 /* Exception stack levels */ +#define MSR_IA32_FRED_SSP0 MSR_IA32_PL0_SSP /* Level 0 shadow stack pointer */ +#define MSR_IA32_FRED_SSP1 0x1d1 /* Level 1 shadow stack pointer */ +#define MSR_IA32_FRED_SSP2 0x1d2 /* Level 2 shadow stack pointer */ +#define MSR_IA32_FRED_SSP3 0x1d3 /* Level 3 shadow stack pointer */ +#define MSR_IA32_FRED_CONFIG 0x1d4 /* Entrypoint and interrupt stack level */ +/* Intel MSRs. Some also available on other CPUs */ #define MSR_TEST_CTRL 0x00000033 #define MSR_TEST_CTRL_SPLIT_LOCK_DETECT_BIT 29 #define MSR_TEST_CTRL_SPLIT_LOCK_DETECT BIT(MSR_TEST_CTRL_SPLIT_LOCK_DETECT_BIT) diff --git a/tools/arch/x86/include/asm/msr-index.h b/tools/arch/x86/include/asm/msr-index.h index 1d111350197f..972d15404420 100644 --- a/tools/arch/x86/include/asm/msr-index.h +++ b/tools/arch/x86/include/asm/msr-index.h @@ -36,8 +36,19 @@ #define EFER_FFXSR (1<<_EFER_FFXSR) #define EFER_AUTOIBRS (1<<_EFER_AUTOIBRS) -/* Intel MSRs. Some also available on other CPUs */ +/* FRED MSRs */ +#define MSR_IA32_FRED_RSP0 0x1cc /* Level 0 stack pointer */ +#define MSR_IA32_FRED_RSP1 0x1cd /* Level 1 stack pointer */ +#define MSR_IA32_FRED_RSP2 0x1ce /* Level 2 stack pointer */ +#define MSR_IA32_FRED_RSP3 0x1cf /* Level 3 stack pointer */ +#define MSR_IA32_FRED_STKLVLS 0x1d0 /* Exception stack levels */ +#define MSR_IA32_FRED_SSP0 MSR_IA32_PL0_SSP /* Level 0 shadow stack pointer */ +#define MSR_IA32_FRED_SSP1 0x1d1 /* Level 1 shadow stack pointer */ +#define MSR_IA32_FRED_SSP2 0x1d2 /* Level 2 shadow stack pointer */ +#define MSR_IA32_FRED_SSP3 0x1d3 /* Level 3 shadow stack pointer */ +#define MSR_IA32_FRED_CONFIG 0x1d4 /* Entrypoint and interrupt stack level */ +/* Intel MSRs. Some also available on other CPUs */ #define MSR_TEST_CTRL 0x00000033 #define MSR_TEST_CTRL_SPLIT_LOCK_DETECT_BIT 29 #define MSR_TEST_CTRL_SPLIT_LOCK_DETECT BIT(MSR_TEST_CTRL_SPLIT_LOCK_DETECT_BIT) From patchwork Tue Oct 3 06:24:36 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Li, Xin3" X-Patchwork-Id: 13406835 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1557BE75428 for ; Tue, 3 Oct 2023 06:54:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239264AbjJCGy5 (ORCPT ); Tue, 3 Oct 2023 02:54:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49958 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239200AbjJCGyw (ORCPT ); Tue, 3 Oct 2023 02:54:52 -0400 Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.126]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AD713F9; Mon, 2 Oct 2023 23:54:45 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1696316085; x=1727852085; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=yFOHuHE47yU8Pv3f7vyK1KueQKaw2/ZJmrjuiwmDzLE=; b=elNytsyJ68php4iMY6AYoEx3Yl/VMYYkeaRCd50j88ZTreMHN6HcwiEo N5OmJaU2PFcq84QcShpI94EicO8bnWRZNwjxVczTPm+T/z8tZGgIoRAE0 0ZPOEN4xFUhQ1OwGEZPMHvwDgX2QUpDgusM3bfLmqKCVCxdQHPp74H9ux E2WhhDgWUuIK90T4Rxv7UKj411zsDVgS4BnWfp/qwglIADHBhihY4RjUe K/yE6g4aL961it1ns/EW+P8aL01BzwpahTQ0fPAk0xmbENe/VFezkWuAn d5br9TPWyLLmzo1rdXM1wCYy+rfXWwbcS/FS3GNovuZB4BgIBrGuSSN/I A==; X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="367858075" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="367858075" Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Oct 2023 23:54:42 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="1081900940" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="1081900940" Received: from unknown (HELO fred..) ([172.25.112.68]) by fmsmga005.fm.intel.com with ESMTP; 02 Oct 2023 23:54:42 -0700 From: Xin Li To: linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-edac@vger.kernel.org, linux-hyperv@vger.kernel.org, kvm@vger.kernel.org, xen-devel@lists.xenproject.org Cc: tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, luto@kernel.org, pbonzini@redhat.com, seanjc@google.com, peterz@infradead.org, jgross@suse.com, ravi.v.shankar@intel.com, mhiramat@kernel.org, andrew.cooper3@citrix.com, jiangshanlai@gmail.com, nik.borisov@suse.com Subject: [PATCH v12 15/37] x86/ptrace: Cleanup the definition of the pt_regs structure Date: Mon, 2 Oct 2023 23:24:36 -0700 Message-Id: <20231003062458.23552-16-xin3.li@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231003062458.23552-1-xin3.li@intel.com> References: <20231003062458.23552-1-xin3.li@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org struct pt_regs is hard to read because the member or section related comments are not aligned with the members. The 'cs' and 'ss' members of pt_regs are type of 'unsigned long' while in reality they are only 16-bit wide. This works so far as the remaining space is unused, but FRED will use the remaining bits for other purposes. To prepare for FRED: - Cleanup the formatting - Convert 'cs' and 'ss' to u16 and embed them into an union with a u64 - Fixup the related printk() format strings Signed-off-by: H. Peter Anvin (Intel) Tested-by: Shan Kang Signed-off-by: Thomas Gleixner Signed-off-by: Xin Li --- arch/x86/entry/vsyscall/vsyscall_64.c | 2 +- arch/x86/include/asm/ptrace.h | 44 +++++++++++++++++++-------- arch/x86/kernel/process_64.c | 2 +- 3 files changed, 33 insertions(+), 15 deletions(-) diff --git a/arch/x86/entry/vsyscall/vsyscall_64.c b/arch/x86/entry/vsyscall/vsyscall_64.c index e0ca8120aea8..a3c0df11d0e6 100644 --- a/arch/x86/entry/vsyscall/vsyscall_64.c +++ b/arch/x86/entry/vsyscall/vsyscall_64.c @@ -76,7 +76,7 @@ static void warn_bad_vsyscall(const char *level, struct pt_regs *regs, if (!show_unhandled_signals) return; - printk_ratelimited("%s%s[%d] %s ip:%lx cs:%lx sp:%lx ax:%lx si:%lx di:%lx\n", + printk_ratelimited("%s%s[%d] %s ip:%lx cs:%x sp:%lx ax:%lx si:%lx di:%lx\n", level, current->comm, task_pid_nr(current), message, regs->ip, regs->cs, regs->sp, regs->ax, regs->si, regs->di); diff --git a/arch/x86/include/asm/ptrace.h b/arch/x86/include/asm/ptrace.h index f4db78b09c8f..f08ea073edd6 100644 --- a/arch/x86/include/asm/ptrace.h +++ b/arch/x86/include/asm/ptrace.h @@ -57,17 +57,19 @@ struct pt_regs { #else /* __i386__ */ struct pt_regs { -/* - * C ABI says these regs are callee-preserved. They aren't saved on kernel entry - * unless syscall needs a complete, fully filled "struct pt_regs". - */ + /* + * C ABI says these regs are callee-preserved. They aren't saved on + * kernel entry unless syscall needs a complete, fully filled + * "struct pt_regs". + */ unsigned long r15; unsigned long r14; unsigned long r13; unsigned long r12; unsigned long bp; unsigned long bx; -/* These regs are callee-clobbered. Always saved on kernel entry. */ + + /* These regs are callee-clobbered. Always saved on kernel entry. */ unsigned long r11; unsigned long r10; unsigned long r9; @@ -77,18 +79,34 @@ struct pt_regs { unsigned long dx; unsigned long si; unsigned long di; -/* - * On syscall entry, this is syscall#. On CPU exception, this is error code. - * On hw interrupt, it's IRQ number: - */ + + /* + * orig_ax is used on entry for: + * - the syscall number (syscall, sysenter, int80) + * - error_code stored by the CPU on traps and exceptions + * - the interrupt number for device interrupts + */ unsigned long orig_ax; -/* Return frame for iretq */ + + /* The IRETQ return frame starts here */ unsigned long ip; - unsigned long cs; + + union { + u64 csx; // The full 64-bit data slot containing CS + u16 cs; // CS selector + }; + unsigned long flags; unsigned long sp; - unsigned long ss; -/* top of stack page */ + + union { + u64 ssx; // The full 64-bit data slot containing SS + u16 ss; // SS selector + }; + + /* + * Top of stack on IDT systems. + */ }; #endif /* !__i386__ */ diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c index 33b268747bb7..0f78b58021bb 100644 --- a/arch/x86/kernel/process_64.c +++ b/arch/x86/kernel/process_64.c @@ -117,7 +117,7 @@ void __show_regs(struct pt_regs *regs, enum show_regs_mode mode, printk("%sFS: %016lx(%04x) GS:%016lx(%04x) knlGS:%016lx\n", log_lvl, fs, fsindex, gs, gsindex, shadowgs); - printk("%sCS: %04lx DS: %04x ES: %04x CR0: %016lx\n", + printk("%sCS: %04x DS: %04x ES: %04x CR0: %016lx\n", log_lvl, regs->cs, ds, es, cr0); printk("%sCR2: %016lx CR3: %016lx CR4: %016lx\n", log_lvl, cr2, cr3, cr4); From patchwork Tue Oct 3 06:24:37 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Li, Xin3" X-Patchwork-Id: 13406838 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 690B2E75439 for ; Tue, 3 Oct 2023 06:55:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239260AbjJCGzG (ORCPT ); Tue, 3 Oct 2023 02:55:06 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49956 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239183AbjJCGyx (ORCPT ); Tue, 3 Oct 2023 02:54:53 -0400 Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.126]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AA6E6107; Mon, 2 Oct 2023 23:54:46 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1696316086; x=1727852086; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=V+OPmxsacyHhQwU2DRsayMn8eLFfcoR2lqYdblOZ50U=; b=kGii2U8rVWjB4mjtPAI+wr5f9N90M6Evml4WUwY4m/tVrW1fDZ8duQmL FRwATYYzX7YSCTGk6uFhsldgvuJE/9P+9Ib5xjxndykaQT6BMQ1Tjd1Xp ppnqq657h2DERj4rtBqIxWFD4F4sM0N/OC7e9lnrgMSMbKMNuaK227gS5 C8lIaJg2D6pbwzvwkx520GPnsY6CWtgZOMAo4eqXYB3TieRTJ6LKTBaKV f49Jz/1DpUdPpX9eqh34G1nqwjlvstiXrqz8ZLhFPaVRiw3vVTm6TWZY/ IuQawgWR1GTSeiaJBwrvDUdAhTaE1QEz0+aWCjCUahRjyecSGR/kphMct g==; X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="367858087" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="367858087" Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Oct 2023 23:54:43 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="1081900943" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="1081900943" Received: from unknown (HELO fred..) ([172.25.112.68]) by fmsmga005.fm.intel.com with ESMTP; 02 Oct 2023 23:54:42 -0700 From: Xin Li To: linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-edac@vger.kernel.org, linux-hyperv@vger.kernel.org, kvm@vger.kernel.org, xen-devel@lists.xenproject.org Cc: tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, luto@kernel.org, pbonzini@redhat.com, seanjc@google.com, peterz@infradead.org, jgross@suse.com, ravi.v.shankar@intel.com, mhiramat@kernel.org, andrew.cooper3@citrix.com, jiangshanlai@gmail.com, nik.borisov@suse.com Subject: [PATCH v12 16/37] x86/ptrace: Add FRED additional information to the pt_regs structure Date: Mon, 2 Oct 2023 23:24:37 -0700 Message-Id: <20231003062458.23552-17-xin3.li@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231003062458.23552-1-xin3.li@intel.com> References: <20231003062458.23552-1-xin3.li@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org FRED defines additional information in the upper 48 bits of cs/ss fields. Therefore add the information definitions into the pt_regs structure. Specially introduce a new structure fred_ss to denote the FRED flags above SS selector, which avoids FRED_SSX_ macros and makes the code simpler and easier to read. Signed-off-by: H. Peter Anvin (Intel) Tested-by: Shan Kang Signed-off-by: Thomas Gleixner Signed-off-by: Xin Li --- Changes since v11: * Add a new structure fred_cs to denote the FRED flags above CS selector as what is done for SS (H. Peter Anvin). Changes since v9: * Introduce a new structure fred_ss to denote the FRED flags above SS selector, which avoids FRED_SSX_ macros and makes the code simpler and easier to read (Thomas Gleixner). * Use type u64 to define FRED bit fields instead of type unsigned int (Thomas Gleixner). Changes since v8: * Reflect stack frame definition changes from FRED spec 3.0 to 5.0. * Use __packed instead of __attribute__((__packed__)) (Borislav Petkov). * Put all comments above the members, like the rest of the file does (Borislav Petkov). Changes since v3: * Rename csl/ssl of the pt_regs structure to csx/ssx (x for extended) (Andrew Cooper). --- arch/x86/include/asm/ptrace.h | 70 ++++++++++++++++++++++++++++++++--- 1 file changed, 65 insertions(+), 5 deletions(-) diff --git a/arch/x86/include/asm/ptrace.h b/arch/x86/include/asm/ptrace.h index f08ea073edd6..5a83fbd9bc0b 100644 --- a/arch/x86/include/asm/ptrace.h +++ b/arch/x86/include/asm/ptrace.h @@ -56,6 +56,50 @@ struct pt_regs { #else /* __i386__ */ +struct fred_cs { + /* CS selector */ + u64 cs : 16, + /* Stack level at event time */ + sl : 2, + /* IBT in WAIT_FOR_ENDBRANCH state */ + wfe : 1, + : 45; +}; + +struct fred_ss { + /* SS selector */ + u64 ss : 16, + /* STI state */ + sti : 1, + /* Set if syscall, sysenter or INT n */ + swevent : 1, + /* Event is NMI type */ + nmi : 1, + : 13, + /* Event vector */ + vector : 8, + : 8, + /* Event type */ + type : 4, + : 4, + /* Event was incident to enclave execution */ + enclave : 1, + /* CPU was in long mode */ + lm : 1, + /* + * Nested exception during FRED delivery, not set + * for #DF. + */ + nested : 1, + : 1, + /* + * The length of the instruction causing the event. + * Only set for INTO, INT1, INT3, INT n, SYSCALL + * and SYSENTER. 0 otherwise. + */ + insnlen : 4; +}; + struct pt_regs { /* * C ABI says these regs are callee-preserved. They aren't saved on @@ -85,6 +129,12 @@ struct pt_regs { * - the syscall number (syscall, sysenter, int80) * - error_code stored by the CPU on traps and exceptions * - the interrupt number for device interrupts + * + * A FRED stack frame starts here: + * 1) It _always_ includes an error code; + * + * 2) The return frame for ERET[US] starts here, but + * the content of orig_ax is ignored. */ unsigned long orig_ax; @@ -92,20 +142,30 @@ struct pt_regs { unsigned long ip; union { - u64 csx; // The full 64-bit data slot containing CS - u16 cs; // CS selector + /* CS selector */ + u16 cs; + /* The extended 64-bit data slot containing CS */ + u64 csx; + /* The FRED CS extension */ + struct fred_cs fred_cs; }; unsigned long flags; unsigned long sp; union { - u64 ssx; // The full 64-bit data slot containing SS - u16 ss; // SS selector + /* SS selector */ + u16 ss; + /* The extended 64-bit data slot containing SS */ + u64 ssx; + /* The FRED SS extension */ + struct fred_ss fred_ss; }; /* - * Top of stack on IDT systems. + * Top of stack on IDT systems, while FRED systems have extra fields + * defined above for storing exception related information, e.g. CR2 or + * DR6. */ }; From patchwork Tue Oct 3 06:24:38 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Li, Xin3" X-Patchwork-Id: 13406839 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id CF576E75436 for ; Tue, 3 Oct 2023 06:55:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239302AbjJCGzF (ORCPT ); Tue, 3 Oct 2023 02:55:05 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37608 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239233AbjJCGyy (ORCPT ); Tue, 3 Oct 2023 02:54:54 -0400 Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.126]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9BBBB115; Mon, 2 Oct 2023 23:54:47 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1696316087; x=1727852087; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=SbR2wCTkousO/IPIjdDUqT7zLHmXpw3IGG9LN/Z2MXU=; b=AT4vIlyTKisB+dhSHYdibnuOBRutW7Sel+S7aORQl8GzfTUxN9MJC7Y6 AuLKJ/1vh4kTMfPiubh/Xhyn0yHGzQKaq47bRVHbqS+Zkix54bwXxoo2m 80Y20UqaJW7lpBztTa1l+molWhwG77Aih9qZveCPVDFl6dqBeJMCuG4bU zN2+wi572338gPnISYW75dmp4bbZPj7Q18NFgboUTzeVN/fbj18E3WSYs Ao7BjB87UVxn9ZG5oygijfE3TDDz96JuPN6Rs/o2HKRskGW8v8unMDzDQ Z3hELrsPDYUoIXDc93FbHkukAySmeoKEIzbsO79H2nMysDk5pKg0yCw2c Q==; X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="367858099" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="367858099" Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Oct 2023 23:54:43 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="1081900946" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="1081900946" Received: from unknown (HELO fred..) ([172.25.112.68]) by fmsmga005.fm.intel.com with ESMTP; 02 Oct 2023 23:54:43 -0700 From: Xin Li To: linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-edac@vger.kernel.org, linux-hyperv@vger.kernel.org, kvm@vger.kernel.org, xen-devel@lists.xenproject.org Cc: tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, luto@kernel.org, pbonzini@redhat.com, seanjc@google.com, peterz@infradead.org, jgross@suse.com, ravi.v.shankar@intel.com, mhiramat@kernel.org, andrew.cooper3@citrix.com, jiangshanlai@gmail.com, nik.borisov@suse.com Subject: [PATCH v12 17/37] x86/fred: Add a new header file for FRED definitions Date: Mon, 2 Oct 2023 23:24:38 -0700 Message-Id: <20231003062458.23552-18-xin3.li@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231003062458.23552-1-xin3.li@intel.com> References: <20231003062458.23552-1-xin3.li@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: "H. Peter Anvin (Intel)" Add a header file for FRED prototypes and definitions. Signed-off-by: H. Peter Anvin (Intel) Tested-by: Shan Kang Signed-off-by: Xin Li --- Changes since v6: * Replace pt_regs csx flags prefix FRED_CSL_ with FRED_CSX_. --- arch/x86/include/asm/fred.h | 68 +++++++++++++++++++++++++++++++++++++ 1 file changed, 68 insertions(+) create mode 100644 arch/x86/include/asm/fred.h diff --git a/arch/x86/include/asm/fred.h b/arch/x86/include/asm/fred.h new file mode 100644 index 000000000000..f514fdb5a39f --- /dev/null +++ b/arch/x86/include/asm/fred.h @@ -0,0 +1,68 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Macros for Flexible Return and Event Delivery (FRED) + */ + +#ifndef ASM_X86_FRED_H +#define ASM_X86_FRED_H + +#include + +#include + +/* + * FRED event return instruction opcodes for ERET{S,U}; supported in + * binutils >= 2.41. + */ +#define ERETS _ASM_BYTES(0xf2,0x0f,0x01,0xca) +#define ERETU _ASM_BYTES(0xf3,0x0f,0x01,0xca) + +/* + * RSP is aligned to a 64-byte boundary before used to push a new stack frame + */ +#define FRED_STACK_FRAME_RSP_MASK _AT(unsigned long, (~0x3f)) + +/* + * Used for the return address for call emulation during code patching, + * and measured in 64-byte cache lines. + */ +#define FRED_CONFIG_REDZONE_AMOUNT 1 +#define FRED_CONFIG_REDZONE (_AT(unsigned long, FRED_CONFIG_REDZONE_AMOUNT) << 6) +#define FRED_CONFIG_INT_STKLVL(l) (_AT(unsigned long, l) << 9) +#define FRED_CONFIG_ENTRYPOINT(p) _AT(unsigned long, (p)) + +#ifndef __ASSEMBLY__ + +#ifdef CONFIG_X86_FRED +#include + +#include + +struct fred_info { + /* Event data: CR2, DR6, ... */ + unsigned long edata; + unsigned long resv; +}; + +/* Full format of the FRED stack frame */ +struct fred_frame { + struct pt_regs regs; + struct fred_info info; +}; + +static __always_inline struct fred_info *fred_info(struct pt_regs *regs) +{ + return &container_of(regs, struct fred_frame, regs)->info; +} + +static __always_inline unsigned long fred_event_data(struct pt_regs *regs) +{ + return fred_info(regs)->edata; +} + +#else /* CONFIG_X86_FRED */ +static __always_inline unsigned long fred_event_data(struct pt_regs *regs) { return 0; } +#endif /* CONFIG_X86_FRED */ +#endif /* !__ASSEMBLY__ */ + +#endif /* ASM_X86_FRED_H */ From patchwork Tue Oct 3 06:24:39 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Li, Xin3" X-Patchwork-Id: 13406836 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id DED45E7542C for ; Tue, 3 Oct 2023 06:54:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239250AbjJCGzA (ORCPT ); Tue, 3 Oct 2023 02:55:00 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50030 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239234AbjJCGyy (ORCPT ); Tue, 3 Oct 2023 02:54:54 -0400 Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.126]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C804311C; Mon, 2 Oct 2023 23:54:47 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1696316088; x=1727852088; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=f4gesqgoemAM7gLIVW0tfHuShJv23oH28+TguMOULZ8=; b=XNx/RclM0xEqw4CBaxkn2NWr1vRqeAqWPKUXPlYHfPZCU1FB6X7fu5yv 4cXQnXvMAtDNTtEoMcOdc26lh08Dmpev0POi5kxfsbD6cX9uhqqJ2S1Kq nIspiYC0AVLwtp4AR+lnzQiK31P57XsqgpQEfn4wxoFXfWsOOP92rSgnN xCRortvC5W4x03HYwZ/UhCuzsJvqv+kJy8xO1btwJYTsFviYg17BXQTgv CwurjzxKUA82mS7NC+ndlBp0RX7ETmlgjQMe9t3FmxKEp2KjAiTlyFDEU 7mX2IR/VxFJD4x4uZRrD9L65iuKUt9+ZoszBqopRV3gDSfbpGGRwYBHjv Q==; X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="367858112" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="367858112" Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Oct 2023 23:54:44 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="1081900951" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="1081900951" Received: from unknown (HELO fred..) ([172.25.112.68]) by fmsmga005.fm.intel.com with ESMTP; 02 Oct 2023 23:54:43 -0700 From: Xin Li To: linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-edac@vger.kernel.org, linux-hyperv@vger.kernel.org, kvm@vger.kernel.org, xen-devel@lists.xenproject.org Cc: tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, luto@kernel.org, pbonzini@redhat.com, seanjc@google.com, peterz@infradead.org, jgross@suse.com, ravi.v.shankar@intel.com, mhiramat@kernel.org, andrew.cooper3@citrix.com, jiangshanlai@gmail.com, nik.borisov@suse.com Subject: [PATCH v12 18/37] x86/fred: Reserve space for the FRED stack frame Date: Mon, 2 Oct 2023 23:24:39 -0700 Message-Id: <20231003062458.23552-19-xin3.li@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231003062458.23552-1-xin3.li@intel.com> References: <20231003062458.23552-1-xin3.li@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: "H. Peter Anvin (Intel)" When using FRED, reserve space at the top of the stack frame, just like i386 does. Signed-off-by: H. Peter Anvin (Intel) Tested-by: Shan Kang Signed-off-by: Xin Li --- arch/x86/include/asm/thread_info.h | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/arch/x86/include/asm/thread_info.h b/arch/x86/include/asm/thread_info.h index d63b02940747..12da7dfd5ef1 100644 --- a/arch/x86/include/asm/thread_info.h +++ b/arch/x86/include/asm/thread_info.h @@ -31,7 +31,9 @@ * In vm86 mode, the hardware frame is much longer still, so add 16 * bytes to make room for the real-mode segments. * - * x86_64 has a fixed-length stack frame. + * x86-64 has a fixed-length stack frame, but it depends on whether + * or not FRED is enabled. Future versions of FRED might make this + * dynamic, but for now it is always 2 words longer. */ #ifdef CONFIG_X86_32 # ifdef CONFIG_VM86 @@ -39,8 +41,12 @@ # else # define TOP_OF_KERNEL_STACK_PADDING 8 # endif -#else -# define TOP_OF_KERNEL_STACK_PADDING 0 +#else /* x86-64 */ +# ifdef CONFIG_X86_FRED +# define TOP_OF_KERNEL_STACK_PADDING (2 * 8) +# else +# define TOP_OF_KERNEL_STACK_PADDING 0 +# endif #endif /* From patchwork Tue Oct 3 06:24:40 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Li, Xin3" X-Patchwork-Id: 13406837 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id AA556E7542F for ; Tue, 3 Oct 2023 06:55:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239227AbjJCGzD (ORCPT ); Tue, 3 Oct 2023 02:55:03 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50068 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239235AbjJCGyy (ORCPT ); Tue, 3 Oct 2023 02:54:54 -0400 Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.126]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7BD9A193; Mon, 2 Oct 2023 23:54:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1696316088; x=1727852088; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=U5v5FfPZcbv+kEeu4BDXYc9n8fkslqM+14uJJDiLwkk=; b=E6xK7K0NwPyTIhln7AoM2Bm+kEYbdK8F3LtCDYeGtxgiiFCM15szhw2h 5lP3lldMGSFsJwOJ7FQS/uL0xvfxdAnvgsWCI0dcIsphGzHp10fJzjLuY oT/PcKRlagcf4Ouh1DtVrCqf76RcN3UuiGkLnMPT6tlqsGzSzDjfNeLuY lEpFfUjDbxeBcJn7/S5lEgmA7WT4I9sDvBZpQORrGIx5t5Y0KiFHvJrcI LoP+lX/1gGOKBYdU5DkBteO6JpoAMugCm5/IYlgrDtnv2+spCWSH/zmC0 MYSpCwi1Zq/BBLeNuAVwWy5AfU+fTmYj+4/+9s+wcmiOtrP9UgNYgjvzu w==; X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="367858125" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="367858125" Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Oct 2023 23:54:44 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="1081900954" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="1081900954" Received: from unknown (HELO fred..) ([172.25.112.68]) by fmsmga005.fm.intel.com with ESMTP; 02 Oct 2023 23:54:44 -0700 From: Xin Li To: linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-edac@vger.kernel.org, linux-hyperv@vger.kernel.org, kvm@vger.kernel.org, xen-devel@lists.xenproject.org Cc: tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, luto@kernel.org, pbonzini@redhat.com, seanjc@google.com, peterz@infradead.org, jgross@suse.com, ravi.v.shankar@intel.com, mhiramat@kernel.org, andrew.cooper3@citrix.com, jiangshanlai@gmail.com, nik.borisov@suse.com Subject: [PATCH v12 19/37] x86/fred: Update MSR_IA32_FRED_RSP0 during task switch Date: Mon, 2 Oct 2023 23:24:40 -0700 Message-Id: <20231003062458.23552-20-xin3.li@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231003062458.23552-1-xin3.li@intel.com> References: <20231003062458.23552-1-xin3.li@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: "H. Peter Anvin (Intel)" MSR_IA32_FRED_RSP0 is used during ring 3 event delivery, and needs to be updated to point to the top of next task stack during task switch. Signed-off-by: H. Peter Anvin (Intel) Tested-by: Shan Kang Signed-off-by: Xin Li --- arch/x86/include/asm/switch_to.h | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/arch/x86/include/asm/switch_to.h b/arch/x86/include/asm/switch_to.h index f42dbf17f52b..c3bd0c0758c9 100644 --- a/arch/x86/include/asm/switch_to.h +++ b/arch/x86/include/asm/switch_to.h @@ -70,9 +70,13 @@ static inline void update_task_stack(struct task_struct *task) #ifdef CONFIG_X86_32 this_cpu_write(cpu_tss_rw.x86_tss.sp1, task->thread.sp0); #else - /* Xen PV enters the kernel on the thread stack. */ - if (cpu_feature_enabled(X86_FEATURE_XENPV)) + if (cpu_feature_enabled(X86_FEATURE_FRED)) { + /* WRMSRNS is a baseline feature for FRED. */ + wrmsrns(MSR_IA32_FRED_RSP0, (unsigned long)task_stack_page(task) + THREAD_SIZE); + } else if (cpu_feature_enabled(X86_FEATURE_XENPV)) { + /* Xen PV enters the kernel on the thread stack. */ load_sp0(task_top_of_stack(task)); + } #endif } From patchwork Tue Oct 3 06:24:41 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: "Li, Xin3" X-Patchwork-Id: 13406840 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id BE36BE75431 for ; Tue, 3 Oct 2023 06:55:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239317AbjJCGzK (ORCPT ); Tue, 3 Oct 2023 02:55:10 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49940 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239261AbjJCGy5 (ORCPT ); Tue, 3 Oct 2023 02:54:57 -0400 Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.126]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5E157E9; Mon, 2 Oct 2023 23:54:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1696316092; x=1727852092; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=HaNFd9+f6o42v45n40NutGcoZldX+CMRVlEU3cDygtg=; b=JtCHFHMEPu5NVDh5XXdAjWkYhp1Lq5sD3SyxPQh4W1RNtsgtOIi9Me31 FIXQuI2z3sv6LmHyqRq2fRIs0e+bzOPv5YKHr4ryYPtyp/n1OfyaWC6hI W0pi84Kt9am7AeYuMSkUIM1h6+K9dg500hi2tjaMgNsG8VyEYfRhp1d96 UrfOktayFp9Z1puWReVzsAfMSvbtwDT3jpLQyOZRyybi/dFgl74We2O24 Yh5gab4z9f7OBV3RvUEne1UJXedjEcPSSFehv1P9ZdEnT1NfyIN19MD5/ NvYeLAFseKRjKOqtsr5NxqCWR2odD02T+Pap+7D2ug+9HOqsSQ7AhXb7l w==; X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="367858139" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="367858139" Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Oct 2023 23:54:45 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="1081900957" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="1081900957" Received: from unknown (HELO fred..) ([172.25.112.68]) by fmsmga005.fm.intel.com with ESMTP; 02 Oct 2023 23:54:44 -0700 From: Xin Li To: linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-edac@vger.kernel.org, linux-hyperv@vger.kernel.org, kvm@vger.kernel.org, xen-devel@lists.xenproject.org Cc: tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, luto@kernel.org, pbonzini@redhat.com, seanjc@google.com, peterz@infradead.org, jgross@suse.com, ravi.v.shankar@intel.com, mhiramat@kernel.org, andrew.cooper3@citrix.com, jiangshanlai@gmail.com, nik.borisov@suse.com Subject: [PATCH v12 20/37] x86/fred: Disallow the swapgs instruction when FRED is enabled Date: Mon, 2 Oct 2023 23:24:41 -0700 Message-Id: <20231003062458.23552-21-xin3.li@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231003062458.23552-1-xin3.li@intel.com> References: <20231003062458.23552-1-xin3.li@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: "H. Peter Anvin (Intel)" SWAPGS is no longer needed thus NOT allowed with FRED because FRED transitions ensure that an operating system can _always_ operate with its own GS base address: - For events that occur in ring 3, FRED event delivery swaps the GS base address with the IA32_KERNEL_GS_BASE MSR. - ERETU (the FRED transition that returns to ring 3) also swaps the GS base address with the IA32_KERNEL_GS_BASE MSR. And the operating system can still setup the GS segment for a user thread without the need of loading a user thread GS with: - Using LKGS, available with FRED, to modify other attributes of the GS segment without compromising its ability always to operate with its own GS base address. - Accessing the GS segment base address for a user thread as before using RDMSR or WRMSR on the IA32_KERNEL_GS_BASE MSR. Note, LKGS loads the GS base address into the IA32_KERNEL_GS_BASE MSR instead of the GS segment’s descriptor cache. As such, the operating system never changes its runtime GS base address. Signed-off-by: H. Peter Anvin (Intel) Tested-by: Shan Kang Signed-off-by: Xin Li --- Changes since v8: * Explain why writing directly to the IA32_KERNEL_GS_BASE MSR is doing the right thing (Thomas Gleixner). --- arch/x86/kernel/process_64.c | 27 +++++++++++++++++++++++++-- 1 file changed, 25 insertions(+), 2 deletions(-) diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c index 0f78b58021bb..4f87f5987ae8 100644 --- a/arch/x86/kernel/process_64.c +++ b/arch/x86/kernel/process_64.c @@ -166,7 +166,29 @@ static noinstr unsigned long __rdgsbase_inactive(void) lockdep_assert_irqs_disabled(); - if (!cpu_feature_enabled(X86_FEATURE_XENPV)) { + /* + * SWAPGS is no longer needed thus NOT allowed with FRED because + * FRED transitions ensure that an operating system can _always_ + * operate with its own GS base address: + * - For events that occur in ring 3, FRED event delivery swaps + * the GS base address with the IA32_KERNEL_GS_BASE MSR. + * - ERETU (the FRED transition that returns to ring 3) also swaps + * the GS base address with the IA32_KERNEL_GS_BASE MSR. + * + * And the operating system can still setup the GS segment for a + * user thread without the need of loading a user thread GS with: + * - Using LKGS, available with FRED, to modify other attributes + * of the GS segment without compromising its ability always to + * operate with its own GS base address. + * - Accessing the GS segment base address for a user thread as + * before using RDMSR or WRMSR on the IA32_KERNEL_GS_BASE MSR. + * + * Note, LKGS loads the GS base address into the IA32_KERNEL_GS_BASE + * MSR instead of the GS segment’s descriptor cache. As such, the + * operating system never changes its runtime GS base address. + */ + if (!cpu_feature_enabled(X86_FEATURE_FRED) && + !cpu_feature_enabled(X86_FEATURE_XENPV)) { native_swapgs(); gsbase = rdgsbase(); native_swapgs(); @@ -191,7 +213,8 @@ static noinstr void __wrgsbase_inactive(unsigned long gsbase) { lockdep_assert_irqs_disabled(); - if (!cpu_feature_enabled(X86_FEATURE_XENPV)) { + if (!cpu_feature_enabled(X86_FEATURE_FRED) && + !cpu_feature_enabled(X86_FEATURE_XENPV)) { native_swapgs(); wrgsbase(gsbase); native_swapgs(); From patchwork Tue Oct 3 06:24:42 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Li, Xin3" X-Patchwork-Id: 13406849 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 86613E75428 for ; Tue, 3 Oct 2023 06:55:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239394AbjJCGze (ORCPT ); Tue, 3 Oct 2023 02:55:34 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50104 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239309AbjJCGzG (ORCPT ); Tue, 3 Oct 2023 02:55:06 -0400 Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.126]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2B8B81B6; Mon, 2 Oct 2023 23:54:54 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1696316095; x=1727852095; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=daicXFK30tmpTUp95RTD2ZQAe5K9xY8zuW1WSEbSaqA=; b=nDnCUFQxZgerOfIkCgM34Px/AXBYzixLOj6nwRha90OvxWgqdBHj/cUw u0YkxfTgcGbxQKVH9xExFNSuVQimlAd7VMpPIJVqXp6m29SscCKI4hNfD 5b7/pGyiL2EsAxE2tRJbmWgadN+lgcFDp3J16Eyq2E82AK2HBLtWMnSTT LTPy0bDAC1kxC4cv00HGmtab2kFk5mfhlcMV463FVoQNilIiRP4aei6yf ZGCepMZ9osq3XAsLe3+42IT0BeaI6gTsMcCWb7o47H0NY0YZQ5ffZdKZZ Ucc0Ig1qNe2uz3njWE/DNQ+JfpQiC89PyfKYiRJqTTLCmClWNgrXdWmcQ w==; X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="367858154" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="367858154" Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Oct 2023 23:54:45 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="1081900963" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="1081900963" Received: from unknown (HELO fred..) ([172.25.112.68]) by fmsmga005.fm.intel.com with ESMTP; 02 Oct 2023 23:54:45 -0700 From: Xin Li To: linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-edac@vger.kernel.org, linux-hyperv@vger.kernel.org, kvm@vger.kernel.org, xen-devel@lists.xenproject.org Cc: tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, luto@kernel.org, pbonzini@redhat.com, seanjc@google.com, peterz@infradead.org, jgross@suse.com, ravi.v.shankar@intel.com, mhiramat@kernel.org, andrew.cooper3@citrix.com, jiangshanlai@gmail.com, nik.borisov@suse.com Subject: [PATCH v12 21/37] x86/fred: No ESPFIX needed when FRED is enabled Date: Mon, 2 Oct 2023 23:24:42 -0700 Message-Id: <20231003062458.23552-22-xin3.li@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231003062458.23552-1-xin3.li@intel.com> References: <20231003062458.23552-1-xin3.li@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: "H. Peter Anvin (Intel)" Because FRED always restores the full value of %rsp, ESPFIX is no longer needed when it's enabled. Signed-off-by: H. Peter Anvin (Intel) Tested-by: Shan Kang Signed-off-by: Xin Li --- arch/x86/kernel/espfix_64.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/arch/x86/kernel/espfix_64.c b/arch/x86/kernel/espfix_64.c index 16f9814c9be0..6726e0473d0b 100644 --- a/arch/x86/kernel/espfix_64.c +++ b/arch/x86/kernel/espfix_64.c @@ -106,6 +106,10 @@ void __init init_espfix_bsp(void) pgd_t *pgd; p4d_t *p4d; + /* FRED systems always restore the full value of %rsp */ + if (cpu_feature_enabled(X86_FEATURE_FRED)) + return; + /* Install the espfix pud into the kernel page directory */ pgd = &init_top_pgt[pgd_index(ESPFIX_BASE_ADDR)]; p4d = p4d_alloc(&init_mm, pgd, ESPFIX_BASE_ADDR); @@ -129,6 +133,10 @@ void init_espfix_ap(int cpu) void *stack_page; pteval_t ptemask; + /* FRED systems always restore the full value of %rsp */ + if (cpu_feature_enabled(X86_FEATURE_FRED)) + return; + /* We only have to do this once... */ if (likely(per_cpu(espfix_stack, cpu))) return; /* Already initialized */ From patchwork Tue Oct 3 06:24:43 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Li, Xin3" X-Patchwork-Id: 13406850 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 27F41E7542E for ; Tue, 3 Oct 2023 06:56:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239288AbjJCG4L (ORCPT ); Tue, 3 Oct 2023 02:56:11 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35156 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230243AbjJCGzu (ORCPT ); Tue, 3 Oct 2023 02:55:50 -0400 Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.126]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 927A9CF7; Mon, 2 Oct 2023 23:55:02 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1696316102; x=1727852102; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=m7R91mzhAyMwuxf88uvtu3V1UGcA6vznqDxNdL57F/c=; b=FdtT006N+CmTdugo9f0Ur8OnsM+Li+bpTa1btmxsFOOOb9e+DtqgSUAk o/jYpD04P10pQ7Ay1GFpw5urcqpoqG7YLTgXGMBwuweRwOiKzEyNoH72Q u5zjDsghgI6O8JXnLa1kC6YTW6pxLyTJGx0Vs46SK+J/FOKijSR82nUok WX4+4OwNcG7Il/1fBGz3mcmLec7zBXyWHjte3C5rLgZM2mBWxdre+/vHv eGXBicCXBH1YFKZp9bZk5hGn/OCfaVUOp/Pm3i4uMEBhnFqo+8dJSYzKo rtDUFmd7tGENHcohGYAbaEbDj12pZvmycmEA4vlAngVY2jSURvYoFwgPa w==; X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="367858169" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="367858169" Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Oct 2023 23:54:46 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="1081900966" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="1081900966" Received: from unknown (HELO fred..) ([172.25.112.68]) by fmsmga005.fm.intel.com with ESMTP; 02 Oct 2023 23:54:45 -0700 From: Xin Li To: linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-edac@vger.kernel.org, linux-hyperv@vger.kernel.org, kvm@vger.kernel.org, xen-devel@lists.xenproject.org Cc: tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, luto@kernel.org, pbonzini@redhat.com, seanjc@google.com, peterz@infradead.org, jgross@suse.com, ravi.v.shankar@intel.com, mhiramat@kernel.org, andrew.cooper3@citrix.com, jiangshanlai@gmail.com, nik.borisov@suse.com Subject: [PATCH v12 22/37] x86/fred: Allow single-step trap and NMI when starting a new task Date: Mon, 2 Oct 2023 23:24:43 -0700 Message-Id: <20231003062458.23552-23-xin3.li@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231003062458.23552-1-xin3.li@intel.com> References: <20231003062458.23552-1-xin3.li@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: "H. Peter Anvin (Intel)" Entering a new task is logically speaking a return from a system call (exec, fork, clone, etc.). As such, if ptrace enables single stepping a single step exception should be allowed to trigger immediately upon entering user space. This is not optional. NMI should *never* be disabled in user space. As such, this is an optional, opportunistic way to catch errors. Allow single-step trap and NMI when starting a new task, thus once the new task enters user space, single-step trap and NMI are both enabled immediately. Signed-off-by: H. Peter Anvin (Intel) Tested-by: Shan Kang Signed-off-by: Xin Li --- Changes since v8: * Use high-order 48 bits above the lowest 16 bit SS only when FRED is enabled (Thomas Gleixner). --- arch/x86/kernel/process_64.c | 38 ++++++++++++++++++++++++++++++------ 1 file changed, 32 insertions(+), 6 deletions(-) diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c index 4f87f5987ae8..c075591b7b46 100644 --- a/arch/x86/kernel/process_64.c +++ b/arch/x86/kernel/process_64.c @@ -56,6 +56,7 @@ #include #include #include +#include #ifdef CONFIG_IA32_EMULATION /* Not included via unistd.h */ #include @@ -528,7 +529,7 @@ void x86_gsbase_write_task(struct task_struct *task, unsigned long gsbase) static void start_thread_common(struct pt_regs *regs, unsigned long new_ip, unsigned long new_sp, - unsigned int _cs, unsigned int _ss, unsigned int _ds) + u16 _cs, u16 _ss, u16 _ds) { WARN_ON_ONCE(regs != current_pt_regs()); @@ -545,11 +546,36 @@ start_thread_common(struct pt_regs *regs, unsigned long new_ip, loadsegment(ds, _ds); load_gs_index(0); - regs->ip = new_ip; - regs->sp = new_sp; - regs->cs = _cs; - regs->ss = _ss; - regs->flags = X86_EFLAGS_IF; + regs->ip = new_ip; + regs->sp = new_sp; + regs->csx = _cs; + regs->ssx = _ss; + /* + * Allow single-step trap and NMI when starting a new task, thus + * once the new task enters user space, single-step trap and NMI + * are both enabled immediately. + * + * Entering a new task is logically speaking a return from a + * system call (exec, fork, clone, etc.). As such, if ptrace + * enables single stepping a single step exception should be + * allowed to trigger immediately upon entering user space. + * This is not optional. + * + * NMI should *never* be disabled in user space. As such, this + * is an optional, opportunistic way to catch errors. + * + * Paranoia: High-order 48 bits above the lowest 16 bit SS are + * discarded by the legacy IRET instruction on all Intel, AMD, + * and Cyrix/Centaur/VIA CPUs, thus can be set unconditionally, + * even when FRED is not enabled. But we choose the safer side + * to use these bits only when FRED is enabled. + */ + if (cpu_feature_enabled(X86_FEATURE_FRED)) { + regs->fred_ss.swevent = true; + regs->fred_ss.nmi = true; + } + + regs->flags = X86_EFLAGS_IF | X86_EFLAGS_FIXED; } void From patchwork Tue Oct 3 06:24:44 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Li, Xin3" X-Patchwork-Id: 13406851 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1647AE7542F for ; Tue, 3 Oct 2023 06:56:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239232AbjJCG4P (ORCPT ); Tue, 3 Oct 2023 02:56:15 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35264 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239349AbjJCGz5 (ORCPT ); Tue, 3 Oct 2023 02:55:57 -0400 Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.126]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6023D10C9; Mon, 2 Oct 2023 23:55:04 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1696316105; x=1727852105; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=vZ6vels66+tC8YRpSCj8dEsAAUPLXovJkO1WpIp9s0Y=; b=eS2QIWAKuLck8ingsWmEsHlazcE79NZGqFVLVIswXnQIt0teHTMojPc4 yY+ntjPD7acGFayNF+q/LPFSLrSUrD3jBUiJgunVc/OZbLqb1IE0xv0qV hrHt6ZsBJF6bdTw8arfelXo0W9M/l+gnztkjr6D6miybtyaRAm0Nr3zBd 35rKq6ZCC/WSSP7e5knULxKa1cNfzAPxW72Y+5Ivz3xUs9VF3BgiZCHue S6F5WAVLWQ6PSxUh8k0D8Caj+riGplMJNOAZybQKvl8ZVC7MMY7q+EH5M Z62oORfJaSLml68uABx2IeEbg8nJLzcGO3AO+QX9kX54rDHlEtiLvIyP6 Q==; X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="367858182" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="367858182" Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Oct 2023 23:54:46 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="1081900971" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="1081900971" Received: from unknown (HELO fred..) ([172.25.112.68]) by fmsmga005.fm.intel.com with ESMTP; 02 Oct 2023 23:54:46 -0700 From: Xin Li To: linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-edac@vger.kernel.org, linux-hyperv@vger.kernel.org, kvm@vger.kernel.org, xen-devel@lists.xenproject.org Cc: tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, luto@kernel.org, pbonzini@redhat.com, seanjc@google.com, peterz@infradead.org, jgross@suse.com, ravi.v.shankar@intel.com, mhiramat@kernel.org, andrew.cooper3@citrix.com, jiangshanlai@gmail.com, nik.borisov@suse.com Subject: [PATCH v12 23/37] x86/fred: Make exc_page_fault() work for FRED Date: Mon, 2 Oct 2023 23:24:44 -0700 Message-Id: <20231003062458.23552-24-xin3.li@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231003062458.23552-1-xin3.li@intel.com> References: <20231003062458.23552-1-xin3.li@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: "H. Peter Anvin (Intel)" On a FRED system, the faulting address (CR2) is passed on the stack, to avoid the problem of transient state. Thus we get the page fault address from the stack instead of CR2. Signed-off-by: H. Peter Anvin (Intel) Tested-by: Shan Kang Signed-off-by: Thomas Gleixner Signed-off-by: Xin Li --- arch/x86/mm/fault.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c index ab778eac1952..7675bc067153 100644 --- a/arch/x86/mm/fault.c +++ b/arch/x86/mm/fault.c @@ -34,6 +34,7 @@ #include /* kvm_handle_async_pf */ #include /* fixup_vdso_exception() */ #include +#include #define CREATE_TRACE_POINTS #include @@ -1516,8 +1517,10 @@ handle_page_fault(struct pt_regs *regs, unsigned long error_code, DEFINE_IDTENTRY_RAW_ERRORCODE(exc_page_fault) { - unsigned long address = read_cr2(); irqentry_state_t state; + unsigned long address; + + address = cpu_feature_enabled(X86_FEATURE_FRED) ? fred_event_data(regs) : read_cr2(); prefetchw(¤t->mm->mmap_lock); From patchwork Tue Oct 3 06:24:45 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Li, Xin3" X-Patchwork-Id: 13406852 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7D44EE75430 for ; Tue, 3 Oct 2023 06:56:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239295AbjJCG4d (ORCPT ); Tue, 3 Oct 2023 02:56:33 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56912 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239422AbjJCG4Z (ORCPT ); Tue, 3 Oct 2023 02:56:25 -0400 Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.126]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9CE2F1735; Mon, 2 Oct 2023 23:55:18 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1696316119; x=1727852119; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=aB9X6AvBbEVqHF8pDqD66jUIoaqA7x/kswu7ifFPwEo=; b=eo12nmdlslp6nKD0z/piea2HOY0U/OALVXmH9NdruPZEla4YkPOMljDw gW82iFq/xtov7HTPi0dxRb3ZHiSNfFQvWbAtDP1M7WgHvq5BxeVHHHrbi BLuKYiUkyRSCeUIUrQtPRc1Z5vRR1H04UXg1oJA1FzwZnAN8xMNtml7T+ 9iAVMNNYUv8b2ZfUVDQiJ+AIACX5al+We6J3bvw44tYc9BRtL0xfJr5RT cxgTFBHtK69UQUk+NV71muuAtpL7gJDKMHF5C43//Oxd0vAliURgTUA36 LPjr9W2i1SLkNnnUPXQLjPdwcxn/hzf+5VyMMmQfTaXN3oR1uFoHFn7GI g==; X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="367858195" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="367858195" Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Oct 2023 23:54:47 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="1081900976" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="1081900976" Received: from unknown (HELO fred..) ([172.25.112.68]) by fmsmga005.fm.intel.com with ESMTP; 02 Oct 2023 23:54:46 -0700 From: Xin Li To: linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-edac@vger.kernel.org, linux-hyperv@vger.kernel.org, kvm@vger.kernel.org, xen-devel@lists.xenproject.org Cc: tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, luto@kernel.org, pbonzini@redhat.com, seanjc@google.com, peterz@infradead.org, jgross@suse.com, ravi.v.shankar@intel.com, mhiramat@kernel.org, andrew.cooper3@citrix.com, jiangshanlai@gmail.com, nik.borisov@suse.com Subject: [PATCH v12 24/37] x86/idtentry: Incorporate definitions/declarations of the FRED entries Date: Mon, 2 Oct 2023 23:24:45 -0700 Message-Id: <20231003062458.23552-25-xin3.li@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231003062458.23552-1-xin3.li@intel.com> References: <20231003062458.23552-1-xin3.li@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org FRED and IDT can share most of the definitions and declarations so that in the majority of cases the actual handler implementation is the same. The differences are the exceptions where FRED stores exception related information on the stack and the sysvec implementations as FRED can handle irqentry/exit() in the dispatcher instead of having it in each handler. Also add stub defines for vectors which are not used due to Kconfig decisions to spare the ifdeffery in the actual FRED dispatch code. Tested-by: Shan Kang Signed-off-by: Thomas Gleixner Signed-off-by: Xin Li --- Changes since v9: * Except NMI/#DB/#MCE, FRED really should share the exception handlers with IDT (Thomas Gleixner). Changes since v8: * Put IDTENTRY changes in a separate patch (Thomas Gleixner). --- arch/x86/include/asm/idtentry.h | 71 +++++++++++++++++++++++++++++---- 1 file changed, 63 insertions(+), 8 deletions(-) diff --git a/arch/x86/include/asm/idtentry.h b/arch/x86/include/asm/idtentry.h index cfca68f6cb84..4f26ee9b8b74 100644 --- a/arch/x86/include/asm/idtentry.h +++ b/arch/x86/include/asm/idtentry.h @@ -13,15 +13,18 @@ #include +typedef void (*idtentry_t)(struct pt_regs *regs); + /** * DECLARE_IDTENTRY - Declare functions for simple IDT entry points * No error code pushed by hardware * @vector: Vector number (ignored for C) * @func: Function name of the entry point * - * Declares three functions: + * Declares four functions: * - The ASM entry point: asm_##func * - The XEN PV trap entry point: xen_##func (maybe unused) + * - The C handler called from the FRED event dispatcher (maybe unused) * - The C handler called from the ASM entry point * * Note: This is the C variant of DECLARE_IDTENTRY(). As the name says it @@ -31,6 +34,7 @@ #define DECLARE_IDTENTRY(vector, func) \ asmlinkage void asm_##func(void); \ asmlinkage void xen_asm_##func(void); \ + void fred_##func(struct pt_regs *regs); \ __visible void func(struct pt_regs *regs) /** @@ -137,6 +141,17 @@ static __always_inline void __##func(struct pt_regs *regs, \ #define DEFINE_IDTENTRY_RAW(func) \ __visible noinstr void func(struct pt_regs *regs) +/** + * DEFINE_FREDENTRY_RAW - Emit code for raw FRED entry points + * @func: Function name of the entry point + * + * @func is called from the FRED event dispatcher with interrupts disabled. + * + * See @DEFINE_IDTENTRY_RAW for further details. + */ +#define DEFINE_FREDENTRY_RAW(func) \ +noinstr void fred_##func(struct pt_regs *regs) + /** * DECLARE_IDTENTRY_RAW_ERRORCODE - Declare functions for raw IDT entry points * Error code pushed by hardware @@ -233,17 +248,27 @@ static noinline void __##func(struct pt_regs *regs, u32 vector) #define DEFINE_IDTENTRY_SYSVEC(func) \ static void __##func(struct pt_regs *regs); \ \ +static __always_inline void instr_##func(struct pt_regs *regs) \ +{ \ + kvm_set_cpu_l1tf_flush_l1d(); \ + run_sysvec_on_irqstack_cond(__##func, regs); \ +} \ + \ __visible noinstr void func(struct pt_regs *regs) \ { \ irqentry_state_t state = irqentry_enter(regs); \ \ instrumentation_begin(); \ - kvm_set_cpu_l1tf_flush_l1d(); \ - run_sysvec_on_irqstack_cond(__##func, regs); \ + instr_##func (regs); \ instrumentation_end(); \ irqentry_exit(regs, state); \ } \ \ +void fred_##func(struct pt_regs *regs) \ +{ \ + instr_##func (regs); \ +} \ + \ static noinline void __##func(struct pt_regs *regs) /** @@ -260,19 +285,29 @@ static noinline void __##func(struct pt_regs *regs) #define DEFINE_IDTENTRY_SYSVEC_SIMPLE(func) \ static __always_inline void __##func(struct pt_regs *regs); \ \ -__visible noinstr void func(struct pt_regs *regs) \ +static __always_inline void instr_##func(struct pt_regs *regs) \ { \ - irqentry_state_t state = irqentry_enter(regs); \ - \ - instrumentation_begin(); \ __irq_enter_raw(); \ kvm_set_cpu_l1tf_flush_l1d(); \ __##func (regs); \ __irq_exit_raw(); \ +} \ + \ +__visible noinstr void func(struct pt_regs *regs) \ +{ \ + irqentry_state_t state = irqentry_enter(regs); \ + \ + instrumentation_begin(); \ + instr_##func (regs); \ instrumentation_end(); \ irqentry_exit(regs, state); \ } \ \ +void fred_##func(struct pt_regs *regs) \ +{ \ + instr_##func (regs); \ +} \ + \ static __always_inline void __##func(struct pt_regs *regs) /** @@ -410,15 +445,18 @@ __visible noinstr void func(struct pt_regs *regs, \ /* C-Code mapping */ #define DECLARE_IDTENTRY_NMI DECLARE_IDTENTRY_RAW #define DEFINE_IDTENTRY_NMI DEFINE_IDTENTRY_RAW +#define DEFINE_FREDENTRY_NMI DEFINE_FREDENTRY_RAW #ifdef CONFIG_X86_64 #define DECLARE_IDTENTRY_MCE DECLARE_IDTENTRY_IST #define DEFINE_IDTENTRY_MCE DEFINE_IDTENTRY_IST #define DEFINE_IDTENTRY_MCE_USER DEFINE_IDTENTRY_NOIST +#define DEFINE_FREDENTRY_MCE DEFINE_FREDENTRY_RAW #define DECLARE_IDTENTRY_DEBUG DECLARE_IDTENTRY_IST #define DEFINE_IDTENTRY_DEBUG DEFINE_IDTENTRY_IST #define DEFINE_IDTENTRY_DEBUG_USER DEFINE_IDTENTRY_NOIST +#define DEFINE_FREDENTRY_DEBUG DEFINE_FREDENTRY_RAW #endif #else /* !__ASSEMBLY__ */ @@ -651,23 +689,36 @@ DECLARE_IDTENTRY(RESCHEDULE_VECTOR, sysvec_reschedule_ipi); DECLARE_IDTENTRY_SYSVEC(REBOOT_VECTOR, sysvec_reboot); DECLARE_IDTENTRY_SYSVEC(CALL_FUNCTION_SINGLE_VECTOR, sysvec_call_function_single); DECLARE_IDTENTRY_SYSVEC(CALL_FUNCTION_VECTOR, sysvec_call_function); +#else +# define fred_sysvec_reschedule_ipi NULL +# define fred_sysvec_reboot NULL +# define fred_sysvec_call_function_single NULL +# define fred_sysvec_call_function NULL #endif #ifdef CONFIG_X86_LOCAL_APIC # ifdef CONFIG_X86_MCE_THRESHOLD DECLARE_IDTENTRY_SYSVEC(THRESHOLD_APIC_VECTOR, sysvec_threshold); +# else +# define fred_sysvec_threshold NULL # endif # ifdef CONFIG_X86_MCE_AMD DECLARE_IDTENTRY_SYSVEC(DEFERRED_ERROR_VECTOR, sysvec_deferred_error); +# else +# define fred_sysvec_deferred_error NULL # endif # ifdef CONFIG_X86_THERMAL_VECTOR DECLARE_IDTENTRY_SYSVEC(THERMAL_APIC_VECTOR, sysvec_thermal); +# else +# define fred_sysvec_thermal NULL # endif # ifdef CONFIG_IRQ_WORK DECLARE_IDTENTRY_SYSVEC(IRQ_WORK_VECTOR, sysvec_irq_work); +# else +# define fred_sysvec_irq_work NULL # endif #endif @@ -675,12 +726,16 @@ DECLARE_IDTENTRY_SYSVEC(IRQ_WORK_VECTOR, sysvec_irq_work); DECLARE_IDTENTRY_SYSVEC(POSTED_INTR_VECTOR, sysvec_kvm_posted_intr_ipi); DECLARE_IDTENTRY_SYSVEC(POSTED_INTR_WAKEUP_VECTOR, sysvec_kvm_posted_intr_wakeup_ipi); DECLARE_IDTENTRY_SYSVEC(POSTED_INTR_NESTED_VECTOR, sysvec_kvm_posted_intr_nested_ipi); +#else +# define fred_sysvec_kvm_posted_intr_ipi NULL +# define fred_sysvec_kvm_posted_intr_wakeup_ipi NULL +# define fred_sysvec_kvm_posted_intr_nested_ipi NULL #endif #if IS_ENABLED(CONFIG_HYPERV) DECLARE_IDTENTRY_SYSVEC(HYPERVISOR_CALLBACK_VECTOR, sysvec_hyperv_callback); DECLARE_IDTENTRY_SYSVEC(HYPERV_REENLIGHTENMENT_VECTOR, sysvec_hyperv_reenlightenment); -DECLARE_IDTENTRY_SYSVEC(HYPERV_STIMER0_VECTOR, sysvec_hyperv_stimer0); +DECLARE_IDTENTRY_SYSVEC(HYPERV_STIMER0_VECTOR, sysvec_hyperv_stimer0); #endif #if IS_ENABLED(CONFIG_ACRN_GUEST) From patchwork Tue Oct 3 06:24:46 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Li, Xin3" X-Patchwork-Id: 13406854 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 170D3E75432 for ; 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([172.25.112.68]) by fmsmga005.fm.intel.com with ESMTP; 02 Oct 2023 23:54:47 -0700 From: Xin Li To: linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-edac@vger.kernel.org, linux-hyperv@vger.kernel.org, kvm@vger.kernel.org, xen-devel@lists.xenproject.org Cc: tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, luto@kernel.org, pbonzini@redhat.com, seanjc@google.com, peterz@infradead.org, jgross@suse.com, ravi.v.shankar@intel.com, mhiramat@kernel.org, andrew.cooper3@citrix.com, jiangshanlai@gmail.com, nik.borisov@suse.com Subject: [PATCH v12 25/37] x86/fred: Add a debug fault entry stub for FRED Date: Mon, 2 Oct 2023 23:24:46 -0700 Message-Id: <20231003062458.23552-26-xin3.li@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231003062458.23552-1-xin3.li@intel.com> References: <20231003062458.23552-1-xin3.li@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: "H. Peter Anvin (Intel)" When occurred on different ring level, i.e., from user or kernel context, #DB needs to be handled on different stack: User #DB on current task stack, while kernel #DB on a dedicated stack. This is exactly how FRED event delivery invokes an exception handler: ring 3 event on level 0 stack, i.e., current task stack; ring 0 event on the #DB dedicated stack specified in the IA32_FRED_STKLVLS MSR. So unlike IDT, the FRED debug exception entry stub doesn't do stack switch. On a FRED system, the debug trap status information (DR6) is passed on the stack, to avoid the problem of transient state. Furthermore, FRED transitions avoid a lot of ugly corner cases the handling of which can, and should be, skipped. The FRED debug trap status information saved on the stack differs from DR6 in both stickiness and polarity; it is exactly in the format which debug_read_clear_dr6() returns for the IDT entry points. Signed-off-by: H. Peter Anvin (Intel) Tested-by: Shan Kang Signed-off-by: Xin Li --- Changes since v9: * Disable #DB to avoid endless recursion and stack overflow when a watchpoint/breakpoint is set in the code path which is executed by #DB handler (Thomas Gleixner). Changes since v1: * call irqentry_nmi_{enter,exit}() in both IDT and FRED debug fault kernel handler (Peter Zijlstra). --- arch/x86/kernel/traps.c | 43 ++++++++++++++++++++++++++++++++++++----- 1 file changed, 38 insertions(+), 5 deletions(-) diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c index c876f1d36a81..848c85208a57 100644 --- a/arch/x86/kernel/traps.c +++ b/arch/x86/kernel/traps.c @@ -50,6 +50,7 @@ #include #include #include +#include #include #include #include @@ -934,8 +935,7 @@ static bool notify_debug(struct pt_regs *regs, unsigned long *dr6) return false; } -static __always_inline void exc_debug_kernel(struct pt_regs *regs, - unsigned long dr6) +static noinstr void exc_debug_kernel(struct pt_regs *regs, unsigned long dr6) { /* * Disable breakpoints during exception handling; recursive exceptions @@ -947,6 +947,11 @@ static __always_inline void exc_debug_kernel(struct pt_regs *regs, * * Entry text is excluded for HW_BP_X and cpu_entry_area, which * includes the entry stack is excluded for everything. + * + * For FRED, nested #DB should just work fine. But when a watchpoint or + * breakpoint is set in the code path which is executed by #DB handler, + * it results in an endless recursion and stack overflow. Thus we stay + * with the IDT approach, i.e., save DR7 and disable #DB. */ unsigned long dr7 = local_db_save(); irqentry_state_t irq_state = irqentry_nmi_enter(regs); @@ -976,7 +981,8 @@ static __always_inline void exc_debug_kernel(struct pt_regs *regs, * Catch SYSENTER with TF set and clear DR_STEP. If this hit a * watchpoint at the same time then that will still be handled. */ - if ((dr6 & DR_STEP) && is_sysenter_singlestep(regs)) + if (!cpu_feature_enabled(X86_FEATURE_FRED) && + (dr6 & DR_STEP) && is_sysenter_singlestep(regs)) dr6 &= ~DR_STEP; /* @@ -1008,8 +1014,7 @@ static __always_inline void exc_debug_kernel(struct pt_regs *regs, local_db_restore(dr7); } -static __always_inline void exc_debug_user(struct pt_regs *regs, - unsigned long dr6) +static noinstr void exc_debug_user(struct pt_regs *regs, unsigned long dr6) { bool icebp; @@ -1093,6 +1098,34 @@ DEFINE_IDTENTRY_DEBUG_USER(exc_debug) { exc_debug_user(regs, debug_read_clear_dr6()); } + +#ifdef CONFIG_X86_FRED +/* + * When occurred on different ring level, i.e., from user or kernel + * context, #DB needs to be handled on different stack: User #DB on + * current task stack, while kernel #DB on a dedicated stack. + * + * This is exactly how FRED event delivery invokes an exception + * handler: ring 3 event on level 0 stack, i.e., current task stack; + * ring 0 event on the #DB dedicated stack specified in the + * IA32_FRED_STKLVLS MSR. So unlike IDT, the FRED debug exception + * entry stub doesn't do stack switch. + */ +DEFINE_FREDENTRY_DEBUG(exc_debug) +{ + /* + * FRED #DB stores DR6 on the stack in the format which + * debug_read_clear_dr6() returns for the IDT entry points. + */ + unsigned long dr6 = fred_event_data(regs); + + if (user_mode(regs)) + exc_debug_user(regs, dr6); + else + exc_debug_kernel(regs, dr6); +} +#endif /* CONFIG_X86_FRED */ + #else /* 32 bit does not have separate entry points. */ DEFINE_IDTENTRY_RAW(exc_debug) From patchwork Tue Oct 3 06:24:47 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Li, Xin3" X-Patchwork-Id: 13406853 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 62121E7542D for ; Tue, 3 Oct 2023 06:56:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239435AbjJCG4g (ORCPT ); Tue, 3 Oct 2023 02:56:36 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57034 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239464AbjJCG40 (ORCPT ); Tue, 3 Oct 2023 02:56:26 -0400 Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.126]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9DCF21B2; Mon, 2 Oct 2023 23:55:28 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1696316129; x=1727852129; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=FcZc1QeKj2isPTwOBVaGNTy+si5WeOaciLFU4yv7EQo=; b=YabQmiE2rUx4dErSR37M2EqgFHIHXiG0Ka0awdSpRllK5SHyst4X/ti6 H5w7T0rGchpemXK3ghfDnpqkC364Jcb/62rEpV0c8Qn7O2I2+InHUarSe JwcT3UJpFWUf9BPTip1QdrjfRDE7dcTi4V3W5WBDeP8SylO/k6Dm0Pwyi ldBIyZdbNfIWDhLZq3Z/8QaS6bN+2gfUdiMJbxlHSZmGhV+I1e0FeyzHM Uenc3iNyS/5EZ/QB8xVlaPWrYIWb5wdO09lyY73WvBWo0fwn+UMnXkU4m rsNBGqzpI3MRSIXskDnvlpnIBGV8NwJ1tDhk2Uo7hgUW3wdHTmMVIW1LS A==; X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="367858229" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="367858229" Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Oct 2023 23:54:48 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="1081900982" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="1081900982" Received: from unknown (HELO fred..) ([172.25.112.68]) by fmsmga005.fm.intel.com with ESMTP; 02 Oct 2023 23:54:47 -0700 From: Xin Li To: linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-edac@vger.kernel.org, linux-hyperv@vger.kernel.org, kvm@vger.kernel.org, xen-devel@lists.xenproject.org Cc: tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, luto@kernel.org, pbonzini@redhat.com, seanjc@google.com, peterz@infradead.org, jgross@suse.com, ravi.v.shankar@intel.com, mhiramat@kernel.org, andrew.cooper3@citrix.com, jiangshanlai@gmail.com, nik.borisov@suse.com Subject: [PATCH v12 26/37] x86/fred: Add a NMI entry stub for FRED Date: Mon, 2 Oct 2023 23:24:47 -0700 Message-Id: <20231003062458.23552-27-xin3.li@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231003062458.23552-1-xin3.li@intel.com> References: <20231003062458.23552-1-xin3.li@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: "H. Peter Anvin (Intel)" On a FRED system, NMIs nest both with themselves and faults, transient information is saved into the stack frame, and NMI unblocking only happens when the stack frame indicates that so should happen. Thus, the NMI entry stub for FRED is really quite small... Signed-off-by: H. Peter Anvin (Intel) Tested-by: Shan Kang Signed-off-by: Xin Li --- arch/x86/kernel/nmi.c | 28 ++++++++++++++++++++++++++++ 1 file changed, 28 insertions(+) diff --git a/arch/x86/kernel/nmi.c b/arch/x86/kernel/nmi.c index a0c551846b35..58843fdf5cd0 100644 --- a/arch/x86/kernel/nmi.c +++ b/arch/x86/kernel/nmi.c @@ -34,6 +34,7 @@ #include #include #include +#include #define CREATE_TRACE_POINTS #include @@ -643,6 +644,33 @@ void nmi_backtrace_stall_check(const struct cpumask *btp) #endif +#ifdef CONFIG_X86_FRED +/* + * With FRED, CR2/DR6 is pushed to #PF/#DB stack frame during FRED + * event delivery, i.e., there is no problem of transient states. + * And NMI unblocking only happens when the stack frame indicates + * that so should happen. + * + * Thus, the NMI entry stub for FRED is really straightforward and + * as simple as most exception handlers. As such, #DB is allowed + * during NMI handling. + */ +DEFINE_FREDENTRY_NMI(exc_nmi) +{ + irqentry_state_t irq_state; + + if (IS_ENABLED(CONFIG_SMP) && arch_cpu_is_offline(smp_processor_id())) + return; + + irq_state = irqentry_nmi_enter(regs); + + inc_irq_stat(__nmi_count); + default_do_nmi(regs); + + irqentry_nmi_exit(regs, irq_state); +} +#endif + void stop_nmi(void) { ignore_nmis++; From patchwork Tue Oct 3 06:24:48 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Li, Xin3" X-Patchwork-Id: 13406861 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id CE8CDE75428 for ; Tue, 3 Oct 2023 06:57:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239303AbjJCG5u (ORCPT ); Tue, 3 Oct 2023 02:57:50 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54994 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239522AbjJCG5l (ORCPT ); Tue, 3 Oct 2023 02:57:41 -0400 Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.126]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 19132AD; Mon, 2 Oct 2023 23:55:28 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1696316129; x=1727852129; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=bNtEfhEic2/4eI6U3F6LZD3GtdQN7TZ08d/4AOd+L9I=; b=Yi/z7nBMIQmwh6m0Mc7MSjp6xVnaZzSN2N9HdApVBXN7+GJYt5tOUB1f 892EA2jb/fEAdRe/MrP2c+p606IPGKwZ0jD8RP2AC728YzjtAr+3HFG71 WMhKimaz7a7SOfxqwpxKzmhUtfWnVVLcN5N4YD77O0uG6yfOS2VcXUQTW tZ+reDa8CcAzMd/uy2DNOPEZIKehddWSu+vPi4alm7jXoQlOyJ3iZ+Wje diFANd6wKgix7mtr/5gXIusL8zvrRTJcP2GWroiBqneKUoH8Wsl0/ySDJ Enp8uMrVpr6aJcrE66No58N5OzebtdnA7X68swasH3WI1gDCydZTIY/Ej w==; X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="367858241" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="367858241" Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Oct 2023 23:54:48 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="1081900986" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="1081900986" Received: from unknown (HELO fred..) ([172.25.112.68]) by fmsmga005.fm.intel.com with ESMTP; 02 Oct 2023 23:54:48 -0700 From: Xin Li To: linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-edac@vger.kernel.org, linux-hyperv@vger.kernel.org, kvm@vger.kernel.org, xen-devel@lists.xenproject.org Cc: tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, luto@kernel.org, pbonzini@redhat.com, seanjc@google.com, peterz@infradead.org, jgross@suse.com, ravi.v.shankar@intel.com, mhiramat@kernel.org, andrew.cooper3@citrix.com, jiangshanlai@gmail.com, nik.borisov@suse.com Subject: [PATCH v12 27/37] x86/fred: Add a machine check entry stub for FRED Date: Mon, 2 Oct 2023 23:24:48 -0700 Message-Id: <20231003062458.23552-28-xin3.li@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231003062458.23552-1-xin3.li@intel.com> References: <20231003062458.23552-1-xin3.li@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Like #DB, when occurred on different ring level, i.e., from user or kernel context, #MCE needs to be handled on different stack: User #MCE on current task stack, while kernel #MCE on a dedicated stack. This is exactly how FRED event delivery invokes an exception handler: ring 3 event on level 0 stack, i.e., current task stack; ring 0 event on the #MCE dedicated stack specified in the IA32_FRED_STKLVLS MSR. So unlike IDT, the FRED machine check entry stub doesn't do stack switch. Tested-by: Shan Kang Signed-off-by: Xin Li --- Changes since v5: * Disallow #DB inside #MCE for robustness sake (Peter Zijlstra). --- arch/x86/kernel/cpu/mce/core.c | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+) diff --git a/arch/x86/kernel/cpu/mce/core.c b/arch/x86/kernel/cpu/mce/core.c index 6f35f724cc14..da0a4a102afe 100644 --- a/arch/x86/kernel/cpu/mce/core.c +++ b/arch/x86/kernel/cpu/mce/core.c @@ -52,6 +52,7 @@ #include #include #include +#include #include "internal.h" @@ -2144,6 +2145,31 @@ DEFINE_IDTENTRY_MCE_USER(exc_machine_check) exc_machine_check_user(regs); local_db_restore(dr7); } + +#ifdef CONFIG_X86_FRED +/* + * When occurred on different ring level, i.e., from user or kernel + * context, #MCE needs to be handled on different stack: User #MCE + * on current task stack, while kernel #MCE on a dedicated stack. + * + * This is exactly how FRED event delivery invokes an exception + * handler: ring 3 event on level 0 stack, i.e., current task stack; + * ring 0 event on the #MCE dedicated stack specified in the + * IA32_FRED_STKLVLS MSR. So unlike IDT, the FRED machine check entry + * stub doesn't do stack switch. + */ +DEFINE_FREDENTRY_MCE(exc_machine_check) +{ + unsigned long dr7; + + dr7 = local_db_save(); + if (user_mode(regs)) + exc_machine_check_user(regs); + else + exc_machine_check_kernel(regs); + local_db_restore(dr7); +} +#endif #else /* 32bit unified entry point */ DEFINE_IDTENTRY_RAW(exc_machine_check) From patchwork Tue Oct 3 06:24:49 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Li, Xin3" X-Patchwork-Id: 13406855 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 93C48E75430 for ; Tue, 3 Oct 2023 06:56:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239469AbjJCG4k (ORCPT ); Tue, 3 Oct 2023 02:56:40 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56844 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239518AbjJCG42 (ORCPT ); Tue, 3 Oct 2023 02:56:28 -0400 Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.126]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4FD1D1BE8; Mon, 2 Oct 2023 23:55:30 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1696316130; x=1727852130; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=cEE0ZUvGytHvigumVumgcYXV8x9y7wId43cb0XPUf88=; b=UarIROs/DSCqLKXOqPfN37l5VyBfuMOGYezdrzyrVkRR+QDXnO3k01KA oBOpfNPfW3fesM4ZAhrEgqJ3TyUDfEFnU3tWfzWv8HstpPPvFVJnz9zek bzwdT07bNrLlJJ2mwitzp8hkPL6by3Rc2rvctrIrPUGN71BBNqmnHdHRW I+zd8hNKjV4S9Jg9J+LbiNPCzFb/LRmuQArirKgJrLD8o1fBWwMoeLY/c M0Q7gmKPXH9K3gbtBp0JN/D5NrGUPNW2Q+KVV3oigit1EuK6biBXLll2D DSGHhfRfPr8ij9+hRjkqJK4BSRVTFfG7J+i29FH6/R/vo7PT3sF1TSUYY Q==; X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="367858253" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="367858253" Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Oct 2023 23:54:49 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="1081900989" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="1081900989" Received: from unknown (HELO fred..) ([172.25.112.68]) by fmsmga005.fm.intel.com with ESMTP; 02 Oct 2023 23:54:48 -0700 From: Xin Li To: linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-edac@vger.kernel.org, linux-hyperv@vger.kernel.org, kvm@vger.kernel.org, xen-devel@lists.xenproject.org Cc: tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, luto@kernel.org, pbonzini@redhat.com, seanjc@google.com, peterz@infradead.org, jgross@suse.com, ravi.v.shankar@intel.com, mhiramat@kernel.org, andrew.cooper3@citrix.com, jiangshanlai@gmail.com, nik.borisov@suse.com Subject: [PATCH v12 28/37] x86/fred: FRED entry/exit and dispatch code Date: Mon, 2 Oct 2023 23:24:49 -0700 Message-Id: <20231003062458.23552-29-xin3.li@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231003062458.23552-1-xin3.li@intel.com> References: <20231003062458.23552-1-xin3.li@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: "H. Peter Anvin (Intel)" The code to actually handle kernel and event entry/exit using FRED. It is split up into two files thus: - entry_64_fred.S contains the actual entrypoints and exit code, and saves and restores registers. - entry_fred.c contains the two-level event dispatch code for FRED. The first-level dispatch is on the event type, and the second-level is on the event vector. Originally-by: Megha Dey Signed-off-by: H. Peter Anvin (Intel) Co-developed-by: Xin Li Tested-by: Shan Kang Signed-off-by: Thomas Gleixner Signed-off-by: Xin Li --- Changes since v10: * Replace "IS_ENABLED(CONFIG_IA32_EMULATION)" with the new ia32_enabled() API (Nikolay Borisov). Changes since v9: * Don't use jump tables, indirect jumps are expensive (Thomas Gleixner). * Except NMI/#DB/#MCE, FRED really can share the exception handlers with IDT (Thomas Gleixner). * Avoid the sysvec_* idt_entry muck, do it at a central place, reuse code instead of blindly copying it, which breaks the performance optimized sysvec entries like reschedule_ipi (Thomas Gleixner). * Add asm_ prefix to FRED asm entry points (Thomas Gleixner). Changes since v8: * Don't do syscall early out in fred_entry_from_user() before there are proper performance numbers and justifications (Thomas Gleixner). * Add the control exception handler to the FRED exception handler table (Thomas Gleixner). * Add ENDBR to the FRED_ENTER asm macro. * Reflect the FRED spec 5.0 change that ERETS and ERETU add 8 to %rsp before popping the return context from the stack. Changes since v1: * Initialize a FRED exception handler to fred_bad_event() instead of NULL if no FRED handler defined for an exception vector (Peter Zijlstra). * Push calling irqentry_{enter,exit}() and instrumentation_{begin,end}() down into individual FRED exception handlers, instead of in the dispatch framework (Peter Zijlstra). --- arch/x86/entry/Makefile | 5 +- arch/x86/entry/entry_64_fred.S | 52 ++++++ arch/x86/entry/entry_fred.c | 230 ++++++++++++++++++++++++++ arch/x86/include/asm/asm-prototypes.h | 1 + arch/x86/include/asm/fred.h | 6 + 5 files changed, 293 insertions(+), 1 deletion(-) create mode 100644 arch/x86/entry/entry_64_fred.S create mode 100644 arch/x86/entry/entry_fred.c diff --git a/arch/x86/entry/Makefile b/arch/x86/entry/Makefile index ca2fe186994b..c93e7f5c2a06 100644 --- a/arch/x86/entry/Makefile +++ b/arch/x86/entry/Makefile @@ -18,6 +18,9 @@ obj-y += vdso/ obj-y += vsyscall/ obj-$(CONFIG_PREEMPTION) += thunk_$(BITS).o +CFLAGS_entry_fred.o += -fno-stack-protector +CFLAGS_REMOVE_entry_fred.o += -pg $(CC_FLAGS_FTRACE) +obj-$(CONFIG_X86_FRED) += entry_64_fred.o entry_fred.o + obj-$(CONFIG_IA32_EMULATION) += entry_64_compat.o syscall_32.o obj-$(CONFIG_X86_X32_ABI) += syscall_x32.o - diff --git a/arch/x86/entry/entry_64_fred.S b/arch/x86/entry/entry_64_fred.S new file mode 100644 index 000000000000..37a1dd5e8ace --- /dev/null +++ b/arch/x86/entry/entry_64_fred.S @@ -0,0 +1,52 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * The actual FRED entry points. + */ + +#include + +#include "calling.h" + + .code64 + .section .noinstr.text, "ax" + +.macro FRED_ENTER + UNWIND_HINT_END_OF_STACK + ENDBR + PUSH_AND_CLEAR_REGS + movq %rsp, %rdi /* %rdi -> pt_regs */ +.endm + +.macro FRED_EXIT + UNWIND_HINT_REGS + POP_REGS +.endm + +/* + * The new RIP value that FRED event delivery establishes is + * IA32_FRED_CONFIG & ~FFFH for events that occur in ring 3. + * Thus the FRED ring 3 entry point must be 4K page aligned. + */ + .align 4096 + +SYM_CODE_START_NOALIGN(asm_fred_entrypoint_user) + FRED_ENTER + call fred_entry_from_user + FRED_EXIT + ERETU +SYM_CODE_END(asm_fred_entrypoint_user) + +.fill asm_fred_entrypoint_kernel - ., 1, 0xcc + +/* + * The new RIP value that FRED event delivery establishes is + * (IA32_FRED_CONFIG & ~FFFH) + 256 for events that occur in + * ring 0, i.e., asm_fred_entrypoint_user + 256. + */ + .org asm_fred_entrypoint_user + 256 +SYM_CODE_START_NOALIGN(asm_fred_entrypoint_kernel) + FRED_ENTER + call fred_entry_from_kernel + FRED_EXIT + ERETS +SYM_CODE_END(asm_fred_entrypoint_kernel) diff --git a/arch/x86/entry/entry_fred.c b/arch/x86/entry/entry_fred.c new file mode 100644 index 000000000000..215883e90f94 --- /dev/null +++ b/arch/x86/entry/entry_fred.c @@ -0,0 +1,230 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * The FRED specific kernel/user entry functions which are invoked from + * assembly code and dispatch to the associated handlers. + */ +#include +#include +#include + +#include +#include +#include +#include +#include +#include + +/* FRED EVENT_TYPE_OTHER vector numbers */ +#define FRED_SYSCALL 1 +#define FRED_SYSENTER 2 + +static noinstr void fred_bad_type(struct pt_regs *regs, unsigned long error_code) +{ + irqentry_state_t irq_state = irqentry_nmi_enter(regs); + + instrumentation_begin(); + + /* Panic on events from a high stack level */ + if (regs->fred_cs.sl > 0) { + pr_emerg("PANIC: invalid or fatal FRED event; event type %u " + "vector %u error 0x%lx aux 0x%lx at %04x:%016lx\n", + regs->fred_ss.type, regs->fred_ss.vector, regs->orig_ax, + fred_event_data(regs), regs->cs, regs->ip); + die("invalid or fatal FRED event", regs, regs->orig_ax); + panic("invalid or fatal FRED event"); + } else { + unsigned long flags = oops_begin(); + int sig = SIGKILL; + + pr_alert("BUG: invalid or fatal FRED event; event type %u " + "vector %u error 0x%lx aux 0x%lx at %04x:%016lx\n", + regs->fred_ss.type, regs->fred_ss.vector, regs->orig_ax, + fred_event_data(regs), regs->cs, regs->ip); + + if (__die("Invalid or fatal FRED event", regs, regs->orig_ax)) + sig = 0; + + oops_end(flags, regs, sig); + } + + instrumentation_end(); + irqentry_nmi_exit(regs, irq_state); +} + +static noinstr void fred_intx(struct pt_regs *regs) +{ + switch (regs->fred_ss.vector) { + /* INT0 */ + case X86_TRAP_OF: + exc_overflow(regs); + return; + + /* INT3 */ + case X86_TRAP_BP: + exc_int3(regs); + return; + + /* INT80 */ + case IA32_SYSCALL_VECTOR: + if (ia32_enabled()) { + /* Save the syscall number */ + regs->orig_ax = regs->ax; + regs->ax = -ENOSYS; + do_int80_syscall_32(regs); + return; + } + fallthrough; + + default: + exc_general_protection(regs, 0); + return; + } +} + +static __always_inline void fred_other(struct pt_regs *regs) +{ + /* The compiler can fold these conditions into a single test */ + if (likely(regs->fred_ss.vector == FRED_SYSCALL && regs->fred_ss.lm)) { + regs->orig_ax = regs->ax; + regs->ax = -ENOSYS; + do_syscall_64(regs, regs->orig_ax); + return; + } else if (ia32_enabled() && + likely(regs->fred_ss.vector == FRED_SYSENTER && + !regs->fred_ss.lm)) { + regs->orig_ax = regs->ax; + regs->ax = -ENOSYS; + do_fast_syscall_32(regs); + return; + } else { + exc_invalid_op(regs); + return; + } +} + +#define SYSVEC(_vector, _function) [_vector - FIRST_SYSTEM_VECTOR] = fred_sysvec_##_function + +static idtentry_t sysvec_table[NR_SYSTEM_VECTORS] __ro_after_init = { + SYSVEC(ERROR_APIC_VECTOR, error_interrupt), + SYSVEC(SPURIOUS_APIC_VECTOR, spurious_apic_interrupt), + SYSVEC(LOCAL_TIMER_VECTOR, apic_timer_interrupt), + SYSVEC(X86_PLATFORM_IPI_VECTOR, x86_platform_ipi), + + SYSVEC(RESCHEDULE_VECTOR, reschedule_ipi), + SYSVEC(CALL_FUNCTION_SINGLE_VECTOR, call_function_single), + SYSVEC(CALL_FUNCTION_VECTOR, call_function), + SYSVEC(REBOOT_VECTOR, reboot), + + SYSVEC(THRESHOLD_APIC_VECTOR, threshold), + SYSVEC(DEFERRED_ERROR_VECTOR, deferred_error), + SYSVEC(THERMAL_APIC_VECTOR, thermal), + + SYSVEC(IRQ_WORK_VECTOR, irq_work), + + SYSVEC(POSTED_INTR_VECTOR, kvm_posted_intr_ipi), + SYSVEC(POSTED_INTR_WAKEUP_VECTOR, kvm_posted_intr_wakeup_ipi), + SYSVEC(POSTED_INTR_NESTED_VECTOR, kvm_posted_intr_nested_ipi), +}; + +static noinstr void fred_extint(struct pt_regs *regs) +{ + unsigned int vector = regs->fred_ss.vector; + + if (WARN_ON_ONCE(vector < FIRST_EXTERNAL_VECTOR)) + return; + + if (likely(vector >= FIRST_SYSTEM_VECTOR)) { + irqentry_state_t state = irqentry_enter(regs); + + instrumentation_begin(); + sysvec_table[vector - FIRST_SYSTEM_VECTOR](regs); + instrumentation_end(); + irqentry_exit(regs, state); + } else { + common_interrupt(regs, vector); + } +} + +static noinstr void fred_exception(struct pt_regs *regs, unsigned long error_code) +{ + /* Optimize for #PF. That's the only exception which matters performance wise */ + if (likely(regs->fred_ss.vector == X86_TRAP_PF)) { + exc_page_fault(regs, error_code); + return; + } + + switch (regs->fred_ss.vector) { + case X86_TRAP_DE: return exc_divide_error(regs); + case X86_TRAP_DB: return fred_exc_debug(regs); + case X86_TRAP_BP: return exc_int3(regs); + case X86_TRAP_OF: return exc_overflow(regs); + case X86_TRAP_BR: return exc_bounds(regs); + case X86_TRAP_UD: return exc_invalid_op(regs); + case X86_TRAP_NM: return exc_device_not_available(regs); + case X86_TRAP_DF: return exc_double_fault(regs, error_code); + case X86_TRAP_TS: return exc_invalid_tss(regs, error_code); + case X86_TRAP_NP: return exc_segment_not_present(regs, error_code); + case X86_TRAP_SS: return exc_stack_segment(regs, error_code); + case X86_TRAP_GP: return exc_general_protection(regs, error_code); + case X86_TRAP_MF: return exc_coprocessor_error(regs); + case X86_TRAP_AC: return exc_alignment_check(regs, error_code); + case X86_TRAP_XF: return exc_simd_coprocessor_error(regs); + +#ifdef CONFIG_X86_MCE + case X86_TRAP_MC: return fred_exc_machine_check(regs); +#endif +#ifdef CONFIG_INTEL_TDX_GUEST + case X86_TRAP_VE: return exc_virtualization_exception(regs); +#endif +#ifdef CONFIG_X86_KERNEL_IBT + case X86_TRAP_CP: return exc_control_protection(regs, error_code); +#endif + default: return fred_bad_type(regs, error_code); + } +} + +__visible noinstr void fred_entry_from_user(struct pt_regs *regs) +{ + unsigned long error_code = regs->orig_ax; + + /* Invalidate orig_ax so that syscall_get_nr() works correctly */ + regs->orig_ax = -1; + + switch (regs->fred_ss.type) { + case EVENT_TYPE_EXTINT: + return fred_extint(regs); + case EVENT_TYPE_NMI: + return fred_exc_nmi(regs); + case EVENT_TYPE_SWINT: + return fred_intx(regs); + case EVENT_TYPE_HWEXC: + case EVENT_TYPE_SWEXC: + case EVENT_TYPE_PRIV_SWEXC: + return fred_exception(regs, error_code); + case EVENT_TYPE_OTHER: + return fred_other(regs); + default: + return fred_bad_type(regs, error_code); + } +} + +__visible noinstr void fred_entry_from_kernel(struct pt_regs *regs) +{ + unsigned long error_code = regs->orig_ax; + + /* Invalidate orig_ax so that syscall_get_nr() works correctly */ + regs->orig_ax = -1; + + switch (regs->fred_ss.type) { + case EVENT_TYPE_EXTINT: + return fred_extint(regs); + case EVENT_TYPE_NMI: + return fred_exc_nmi(regs); + case EVENT_TYPE_HWEXC: + case EVENT_TYPE_SWEXC: + case EVENT_TYPE_PRIV_SWEXC: + return fred_exception(regs, error_code); + default: + return fred_bad_type(regs, error_code); + } +} diff --git a/arch/x86/include/asm/asm-prototypes.h b/arch/x86/include/asm/asm-prototypes.h index b1a98fa38828..076bf8dee702 100644 --- a/arch/x86/include/asm/asm-prototypes.h +++ b/arch/x86/include/asm/asm-prototypes.h @@ -12,6 +12,7 @@ #include #include #include +#include #include #ifndef CONFIG_X86_CMPXCHG64 diff --git a/arch/x86/include/asm/fred.h b/arch/x86/include/asm/fred.h index f514fdb5a39f..16a64ffecbf8 100644 --- a/arch/x86/include/asm/fred.h +++ b/arch/x86/include/asm/fred.h @@ -60,6 +60,12 @@ static __always_inline unsigned long fred_event_data(struct pt_regs *regs) return fred_info(regs)->edata; } +void asm_fred_entrypoint_user(void); +void asm_fred_entrypoint_kernel(void); + +__visible void fred_entry_from_user(struct pt_regs *regs); +__visible void fred_entry_from_kernel(struct pt_regs *regs); + #else /* CONFIG_X86_FRED */ static __always_inline unsigned long fred_event_data(struct pt_regs *regs) { return 0; } #endif /* CONFIG_X86_FRED */ From patchwork Tue Oct 3 06:24:50 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Li, Xin3" X-Patchwork-Id: 13406856 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1753CE75430 for ; Tue, 3 Oct 2023 06:56:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239527AbjJCG4x (ORCPT ); Tue, 3 Oct 2023 02:56:53 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57230 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239564AbjJCG4b (ORCPT ); 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([172.25.112.68]) by fmsmga005.fm.intel.com with ESMTP; 02 Oct 2023 23:54:49 -0700 From: Xin Li To: linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-edac@vger.kernel.org, linux-hyperv@vger.kernel.org, kvm@vger.kernel.org, xen-devel@lists.xenproject.org Cc: tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, luto@kernel.org, pbonzini@redhat.com, seanjc@google.com, peterz@infradead.org, jgross@suse.com, ravi.v.shankar@intel.com, mhiramat@kernel.org, andrew.cooper3@citrix.com, jiangshanlai@gmail.com, nik.borisov@suse.com Subject: [PATCH v12 29/37] x86/traps: Add sysvec_install() to install a system interrupt handler Date: Mon, 2 Oct 2023 23:24:50 -0700 Message-Id: <20231003062458.23552-30-xin3.li@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231003062458.23552-1-xin3.li@intel.com> References: <20231003062458.23552-1-xin3.li@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Add sysvec_install() to install a system interrupt handler into the IDT or the FRED system interrupt handler table. Tested-by: Shan Kang Signed-off-by: Xin Li --- Changes since v8: * Introduce a macro sysvec_install() to derive the asm handler name from a C handler, which simplifies the code and avoids an ugly typecast (Thomas Gleixner). --- arch/x86/entry/entry_fred.c | 14 ++++++++++++++ arch/x86/include/asm/desc.h | 2 -- arch/x86/include/asm/idtentry.h | 15 +++++++++++++++ arch/x86/kernel/cpu/acrn.c | 4 ++-- arch/x86/kernel/cpu/mshyperv.c | 15 +++++++-------- arch/x86/kernel/idt.c | 4 ++-- arch/x86/kernel/kvm.c | 2 +- drivers/xen/events/events_base.c | 2 +- 8 files changed, 42 insertions(+), 16 deletions(-) diff --git a/arch/x86/entry/entry_fred.c b/arch/x86/entry/entry_fred.c index 215883e90f94..e80e3efbc057 100644 --- a/arch/x86/entry/entry_fred.c +++ b/arch/x86/entry/entry_fred.c @@ -126,6 +126,20 @@ static idtentry_t sysvec_table[NR_SYSTEM_VECTORS] __ro_after_init = { SYSVEC(POSTED_INTR_NESTED_VECTOR, kvm_posted_intr_nested_ipi), }; +static bool fred_setup_done __initdata; + +void __init fred_install_sysvec(unsigned int sysvec, idtentry_t handler) +{ + if (WARN_ON_ONCE(sysvec < FIRST_SYSTEM_VECTOR)) + return; + + if (WARN_ON_ONCE(fred_setup_done)) + return; + + if (!WARN_ON_ONCE(sysvec_table[sysvec - FIRST_SYSTEM_VECTOR])) + sysvec_table[sysvec - FIRST_SYSTEM_VECTOR] = handler; +} + static noinstr void fred_extint(struct pt_regs *regs) { unsigned int vector = regs->fred_ss.vector; diff --git a/arch/x86/include/asm/desc.h b/arch/x86/include/asm/desc.h index ab97b22ac04a..ec95fe44fa3a 100644 --- a/arch/x86/include/asm/desc.h +++ b/arch/x86/include/asm/desc.h @@ -402,8 +402,6 @@ static inline void set_desc_limit(struct desc_struct *desc, unsigned long limit) desc->limit1 = (limit >> 16) & 0xf; } -void alloc_intr_gate(unsigned int n, const void *addr); - static inline void init_idt_data(struct idt_data *data, unsigned int n, const void *addr) { diff --git a/arch/x86/include/asm/idtentry.h b/arch/x86/include/asm/idtentry.h index 4f26ee9b8b74..650c98160152 100644 --- a/arch/x86/include/asm/idtentry.h +++ b/arch/x86/include/asm/idtentry.h @@ -459,6 +459,21 @@ __visible noinstr void func(struct pt_regs *regs, \ #define DEFINE_FREDENTRY_DEBUG DEFINE_FREDENTRY_RAW #endif +void idt_install_sysvec(unsigned int n, const void *function); + +#ifdef CONFIG_X86_FRED +void fred_install_sysvec(unsigned int vector, const idtentry_t function); +#else +static inline void fred_install_sysvec(unsigned int vector, const idtentry_t function) { } +#endif + +#define sysvec_install(vector, function) { \ + if (cpu_feature_enabled(X86_FEATURE_FRED)) \ + fred_install_sysvec(vector, function); \ + else \ + idt_install_sysvec(vector, asm_##function); \ +} + #else /* !__ASSEMBLY__ */ /* diff --git a/arch/x86/kernel/cpu/acrn.c b/arch/x86/kernel/cpu/acrn.c index bfeb18fad63f..2c5b51aad91a 100644 --- a/arch/x86/kernel/cpu/acrn.c +++ b/arch/x86/kernel/cpu/acrn.c @@ -26,8 +26,8 @@ static u32 __init acrn_detect(void) static void __init acrn_init_platform(void) { - /* Setup the IDT for ACRN hypervisor callback */ - alloc_intr_gate(HYPERVISOR_CALLBACK_VECTOR, asm_sysvec_acrn_hv_callback); + /* Install system interrupt handler for ACRN hypervisor callback */ + sysvec_install(HYPERVISOR_CALLBACK_VECTOR, sysvec_acrn_hv_callback); x86_platform.calibrate_tsc = acrn_get_tsc_khz; x86_platform.calibrate_cpu = acrn_get_tsc_khz; diff --git a/arch/x86/kernel/cpu/mshyperv.c b/arch/x86/kernel/cpu/mshyperv.c index e6bba12c759c..3403880c3e09 100644 --- a/arch/x86/kernel/cpu/mshyperv.c +++ b/arch/x86/kernel/cpu/mshyperv.c @@ -536,19 +536,18 @@ static void __init ms_hyperv_init_platform(void) */ x86_platform.apic_post_init = hyperv_init; hyperv_setup_mmu_ops(); - /* Setup the IDT for hypervisor callback */ - alloc_intr_gate(HYPERVISOR_CALLBACK_VECTOR, asm_sysvec_hyperv_callback); - /* Setup the IDT for reenlightenment notifications */ + /* Install system interrupt handler for hypervisor callback */ + sysvec_install(HYPERVISOR_CALLBACK_VECTOR, sysvec_hyperv_callback); + + /* Install system interrupt handler for reenlightenment notifications */ if (ms_hyperv.features & HV_ACCESS_REENLIGHTENMENT) { - alloc_intr_gate(HYPERV_REENLIGHTENMENT_VECTOR, - asm_sysvec_hyperv_reenlightenment); + sysvec_install(HYPERV_REENLIGHTENMENT_VECTOR, sysvec_hyperv_reenlightenment); } - /* Setup the IDT for stimer0 */ + /* Install system interrupt handler for stimer0 */ if (ms_hyperv.misc_features & HV_STIMER_DIRECT_MODE_AVAILABLE) { - alloc_intr_gate(HYPERV_STIMER0_VECTOR, - asm_sysvec_hyperv_stimer0); + sysvec_install(HYPERV_STIMER0_VECTOR, sysvec_hyperv_stimer0); } # ifdef CONFIG_SMP diff --git a/arch/x86/kernel/idt.c b/arch/x86/kernel/idt.c index 8857abc706e4..2b734927eec1 100644 --- a/arch/x86/kernel/idt.c +++ b/arch/x86/kernel/idt.c @@ -337,7 +337,7 @@ void idt_invalidate(void) load_idt(&idt); } -void __init alloc_intr_gate(unsigned int n, const void *addr) +void __init idt_install_sysvec(unsigned int n, const void *function) { if (WARN_ON(n < FIRST_SYSTEM_VECTOR)) return; @@ -346,5 +346,5 @@ void __init alloc_intr_gate(unsigned int n, const void *addr) return; if (!WARN_ON(test_and_set_bit(n, system_vectors))) - set_intr_gate(n, addr); + set_intr_gate(n, function); } diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c index b8ab9ee5896c..eabf03813a5c 100644 --- a/arch/x86/kernel/kvm.c +++ b/arch/x86/kernel/kvm.c @@ -829,7 +829,7 @@ static void __init kvm_guest_init(void) if (kvm_para_has_feature(KVM_FEATURE_ASYNC_PF_INT) && kvmapf) { static_branch_enable(&kvm_async_pf_enabled); - alloc_intr_gate(HYPERVISOR_CALLBACK_VECTOR, asm_sysvec_kvm_asyncpf_interrupt); + sysvec_install(HYPERVISOR_CALLBACK_VECTOR, sysvec_kvm_asyncpf_interrupt); } #ifdef CONFIG_SMP diff --git a/drivers/xen/events/events_base.c b/drivers/xen/events/events_base.c index 0bb86e6c4d0a..4bd1293e666f 100644 --- a/drivers/xen/events/events_base.c +++ b/drivers/xen/events/events_base.c @@ -2226,7 +2226,7 @@ static __init void xen_alloc_callback_vector(void) return; pr_info("Xen HVM callback vector for event delivery is enabled\n"); - alloc_intr_gate(HYPERVISOR_CALLBACK_VECTOR, asm_sysvec_xen_hvm_callback); + sysvec_install(HYPERVISOR_CALLBACK_VECTOR, sysvec_xen_hvm_callback); } #else void xen_setup_callback_vector(void) {} From patchwork Tue Oct 3 06:24:51 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Li, Xin3" X-Patchwork-Id: 13406860 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 06929E7542F for ; 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([172.25.112.68]) by fmsmga005.fm.intel.com with ESMTP; 02 Oct 2023 23:54:49 -0700 From: Xin Li To: linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-edac@vger.kernel.org, linux-hyperv@vger.kernel.org, kvm@vger.kernel.org, xen-devel@lists.xenproject.org Cc: tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, luto@kernel.org, pbonzini@redhat.com, seanjc@google.com, peterz@infradead.org, jgross@suse.com, ravi.v.shankar@intel.com, mhiramat@kernel.org, andrew.cooper3@citrix.com, jiangshanlai@gmail.com, nik.borisov@suse.com Subject: [PATCH v12 30/37] x86/fred: Let ret_from_fork_asm() jmp to asm_fred_exit_user when FRED is enabled Date: Mon, 2 Oct 2023 23:24:51 -0700 Message-Id: <20231003062458.23552-31-xin3.li@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231003062458.23552-1-xin3.li@intel.com> References: <20231003062458.23552-1-xin3.li@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: "H. Peter Anvin (Intel)" Let ret_from_fork_asm() jmp to asm_fred_exit_user when FRED is enabled, otherwise the existing IDT code is chosen. Signed-off-by: H. Peter Anvin (Intel) Tested-by: Shan Kang Signed-off-by: Xin Li --- arch/x86/entry/entry_64.S | 6 ++++++ arch/x86/entry/entry_64_fred.S | 1 + 2 files changed, 7 insertions(+) diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S index aa4214703091..7f408deef00f 100644 --- a/arch/x86/entry/entry_64.S +++ b/arch/x86/entry/entry_64.S @@ -309,7 +309,13 @@ SYM_CODE_START(ret_from_fork_asm) * and unwind should work normally. */ UNWIND_HINT_REGS + +#ifdef CONFIG_X86_FRED + ALTERNATIVE "jmp swapgs_restore_regs_and_return_to_usermode", \ + "jmp asm_fred_exit_user", X86_FEATURE_FRED +#else jmp swapgs_restore_regs_and_return_to_usermode +#endif SYM_CODE_END(ret_from_fork_asm) .popsection diff --git a/arch/x86/entry/entry_64_fred.S b/arch/x86/entry/entry_64_fred.S index 37a1dd5e8ace..5781c3411b44 100644 --- a/arch/x86/entry/entry_64_fred.S +++ b/arch/x86/entry/entry_64_fred.S @@ -32,6 +32,7 @@ SYM_CODE_START_NOALIGN(asm_fred_entrypoint_user) FRED_ENTER call fred_entry_from_user +SYM_INNER_LABEL(asm_fred_exit_user, SYM_L_GLOBAL) FRED_EXIT ERETU SYM_CODE_END(asm_fred_entrypoint_user) From patchwork Tue Oct 3 06:24:52 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Li, Xin3" X-Patchwork-Id: 13406857 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4DF8CE75430 for ; Tue, 3 Oct 2023 06:57:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239215AbjJCG5E (ORCPT ); Tue, 3 Oct 2023 02:57:04 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57352 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231184AbjJCG4c (ORCPT ); Tue, 3 Oct 2023 02:56:32 -0400 Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.126]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A053426BD; Mon, 2 Oct 2023 23:55:43 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1696316144; x=1727852144; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=t7LG5n12hETRnrxNhjk5swu4X1wUVGmoU9KoK3uS4dI=; b=F1e+pEtaxnJ4Oy4HH1bj8o0e/1Fxr8DEvXvgTJG0d9XdFrJvzDDuQoUI rXqrX9USAKXOrfNzgdND4gdinckRyOMB7DP7hUAkeuuqUuwQy3CDWnaSb Rjzx7aIHy4Xv+7g5DakwGQ/ChRtl7z9I7nL7209/AESE7pf8ES3Sw3FGg 2ExgD6tMY6LGGu2qrRG5ZRE0UUDHoZ//PSeT48uAyTYLc/HV4SZeb4MF6 Jz8uVNi3ILQ7pvrAQg0kZTi1719yqzW6A+nZf+aCKQLYLgB9JNJaFzRxi VHETW7dUHbjCZU45i8PJOCUhtmwPihjKe8FFSm+i7DHDnVWe1HfouAyPv w==; X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="367858294" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="367858294" Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Oct 2023 23:54:50 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="1081901001" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="1081901001" Received: from unknown (HELO fred..) ([172.25.112.68]) by fmsmga005.fm.intel.com with ESMTP; 02 Oct 2023 23:54:50 -0700 From: Xin Li To: linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-edac@vger.kernel.org, linux-hyperv@vger.kernel.org, kvm@vger.kernel.org, xen-devel@lists.xenproject.org Cc: tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, luto@kernel.org, pbonzini@redhat.com, seanjc@google.com, peterz@infradead.org, jgross@suse.com, ravi.v.shankar@intel.com, mhiramat@kernel.org, andrew.cooper3@citrix.com, jiangshanlai@gmail.com, nik.borisov@suse.com Subject: [PATCH v12 31/37] x86/fred: Fixup fault on ERETU by jumping to fred_entrypoint_user Date: Mon, 2 Oct 2023 23:24:52 -0700 Message-Id: <20231003062458.23552-32-xin3.li@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231003062458.23552-1-xin3.li@intel.com> References: <20231003062458.23552-1-xin3.li@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org If the stack frame contains an invalid user context (e.g. due to invalid SS, a non-canonical RIP, etc.) the ERETU instruction will trap (#SS or #GP). From a Linux point of view, this really should be considered a user space failure, so use the standard fault fixup mechanism to intercept the fault, fix up the exception frame, and redirect execution to fred_entrypoint_user. The end result is that it appears just as if the hardware had taken the exception immediately after completing the transition to user space. Suggested-by: H. Peter Anvin (Intel) Tested-by: Shan Kang Signed-off-by: Xin Li --- Changes since v8: * Reflect the FRED spec 5.0 change that ERETS and ERETU add 8 to %rsp before popping the return context from the stack. Changes since v6: * Add a comment to explain why it is safe to write to the previous FRED stack frame. (Lai Jiangshan). Changes since v5: * Move the NMI bit from an invalid stack frame, which caused ERETU to fault, to the fault handler's stack frame, thus to unblock NMI ASAP if NMI is blocked (Lai Jiangshan). --- arch/x86/entry/entry_64_fred.S | 5 +- arch/x86/include/asm/extable_fixup_types.h | 4 +- arch/x86/mm/extable.c | 79 ++++++++++++++++++++++ 3 files changed, 86 insertions(+), 2 deletions(-) diff --git a/arch/x86/entry/entry_64_fred.S b/arch/x86/entry/entry_64_fred.S index 5781c3411b44..d1c2fc4af8ae 100644 --- a/arch/x86/entry/entry_64_fred.S +++ b/arch/x86/entry/entry_64_fred.S @@ -3,6 +3,7 @@ * The actual FRED entry points. */ +#include #include #include "calling.h" @@ -34,7 +35,9 @@ SYM_CODE_START_NOALIGN(asm_fred_entrypoint_user) call fred_entry_from_user SYM_INNER_LABEL(asm_fred_exit_user, SYM_L_GLOBAL) FRED_EXIT - ERETU +1: ERETU + + _ASM_EXTABLE_TYPE(1b, asm_fred_entrypoint_user, EX_TYPE_ERETU) SYM_CODE_END(asm_fred_entrypoint_user) .fill asm_fred_entrypoint_kernel - ., 1, 0xcc diff --git a/arch/x86/include/asm/extable_fixup_types.h b/arch/x86/include/asm/extable_fixup_types.h index 991e31cfde94..1585c798a02f 100644 --- a/arch/x86/include/asm/extable_fixup_types.h +++ b/arch/x86/include/asm/extable_fixup_types.h @@ -64,6 +64,8 @@ #define EX_TYPE_UCOPY_LEN4 (EX_TYPE_UCOPY_LEN | EX_DATA_IMM(4)) #define EX_TYPE_UCOPY_LEN8 (EX_TYPE_UCOPY_LEN | EX_DATA_IMM(8)) -#define EX_TYPE_ZEROPAD 20 /* longword load with zeropad on fault */ +#define EX_TYPE_ZEROPAD 20 /* longword load with zeropad on fault */ + +#define EX_TYPE_ERETU 21 #endif diff --git a/arch/x86/mm/extable.c b/arch/x86/mm/extable.c index 271dcb2deabc..fc40a4e12f3a 100644 --- a/arch/x86/mm/extable.c +++ b/arch/x86/mm/extable.c @@ -6,6 +6,7 @@ #include #include +#include #include #include #include @@ -223,6 +224,80 @@ static bool ex_handler_ucopy_len(const struct exception_table_entry *fixup, return ex_handler_uaccess(fixup, regs, trapnr, fault_address); } +#ifdef CONFIG_X86_FRED +static bool ex_handler_eretu(const struct exception_table_entry *fixup, + struct pt_regs *regs, unsigned long error_code) +{ + struct pt_regs *uregs = (struct pt_regs *) + (regs->sp - offsetof(struct pt_regs, orig_ax)); + unsigned short ss = uregs->ss; + unsigned short cs = uregs->cs; + + /* + * Move the NMI bit from the invalid stack frame, which caused ERETU + * to fault, to the fault handler's stack frame, thus to unblock NMI + * with the fault handler's ERETS instruction ASAP if NMI is blocked. + */ + regs->fred_ss.nmi = uregs->fred_ss.nmi; + + /* + * Sync event information to uregs, i.e., the ERETU return frame, but + * is it safe to write to the ERETU return frame which is just above + * current event stack frame? + * + * The RSP used by FRED to push a stack frame is not the value in %rsp, + * it is calculated from %rsp with the following 2 steps: + * 1) RSP = %rsp - (IA32_FRED_CONFIG & 0x1c0) // Reserve N*64 bytes + * 2) RSP = RSP & ~0x3f // Align to a 64-byte cache line + * when an event delivery doesn't trigger a stack level change. + * + * Here is an example with N*64 (N=1) bytes reserved: + * + * 64-byte cache line ==> ______________ + * |___Reserved___| + * |__Event_data__| + * |_____SS_______| + * |_____RSP______| + * |_____FLAGS____| + * |_____CS_______| + * |_____IP_______| + * 64-byte cache line ==> |__Error_code__| <== ERETU return frame + * |______________| + * |______________| + * |______________| + * |______________| + * |______________| + * |______________| + * |______________| + * 64-byte cache line ==> |______________| <== RSP after step 1) and 2) + * |___Reserved___| + * |__Event_data__| + * |_____SS_______| + * |_____RSP______| + * |_____FLAGS____| + * |_____CS_______| + * |_____IP_______| + * 64-byte cache line ==> |__Error_code__| <== ERETS return frame + * + * Thus a new FRED stack frame will always be pushed below a previous + * FRED stack frame ((N*64) bytes may be reserved between), and it is + * safe to write to a previous FRED stack frame as they never overlap. + */ + fred_info(uregs)->edata = fred_event_data(regs); + uregs->ssx = regs->ssx; + uregs->fred_ss.ss = ss; + /* The NMI bit was moved away above */ + uregs->fred_ss.nmi = 0; + uregs->csx = regs->csx; + uregs->fred_cs.sl = 0; + uregs->fred_cs.wfe = 0; + uregs->cs = cs; + uregs->orig_ax = error_code; + + return ex_handler_default(fixup, regs); +} +#endif + int ex_get_fixup_type(unsigned long ip) { const struct exception_table_entry *e = search_exception_tables(ip); @@ -300,6 +375,10 @@ int fixup_exception(struct pt_regs *regs, int trapnr, unsigned long error_code, return ex_handler_ucopy_len(e, regs, trapnr, fault_addr, reg, imm); case EX_TYPE_ZEROPAD: return ex_handler_zeropad(e, regs, fault_addr); +#ifdef CONFIG_X86_FRED + case EX_TYPE_ERETU: + return ex_handler_eretu(e, regs, error_code); +#endif } BUG(); } From patchwork Tue Oct 3 06:24:53 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Li, Xin3" X-Patchwork-Id: 13406864 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B08FEE75428 for ; Tue, 3 Oct 2023 06:58:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239572AbjJCG6v (ORCPT ); Tue, 3 Oct 2023 02:58:51 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44568 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239187AbjJCG6h (ORCPT ); Tue, 3 Oct 2023 02:58:37 -0400 Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.126]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E8A312721; Mon, 2 Oct 2023 23:55:46 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1696316147; x=1727852147; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=/UldAmuJEnsflYS2+cyLAQ4E+J1yAKX8pToUnF0eneI=; b=mzyYokYvPpfU+XH4AQorFYfpIEOHM6rXxgiUlcxEAn6yqCRrt6yzMoLC M3gdwzho3vwZmBLsB1rjHq723tRSgYDK6lRZuQQU+TCiR50g7EQKF4avt 6oEixQ3Sc/55SioaPfoDKUmadMddzGVrxu8GDzUgYOHuEGPFqZPnnkYBg b+ALdUhPF1V51fxjRl94kYODRKDwhqHzg79olq7MYwJwFAf0BzpvTSv7A txmFEnLYXPNQTfrGYwjlynqoMHfU6T9jvRA59YvxLjFqUgEVhgfuIM+KS ie5Nk2c1o5rq3ilIu5yskAYXjcbOXnretxnsBPr9WlwNJ3FwCAHd/KIvz Q==; X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="367858304" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="367858304" Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Oct 2023 23:54:51 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="1081901004" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="1081901004" Received: from unknown (HELO fred..) ([172.25.112.68]) by fmsmga005.fm.intel.com with ESMTP; 02 Oct 2023 23:54:50 -0700 From: Xin Li To: linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-edac@vger.kernel.org, linux-hyperv@vger.kernel.org, kvm@vger.kernel.org, xen-devel@lists.xenproject.org Cc: tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, luto@kernel.org, pbonzini@redhat.com, seanjc@google.com, peterz@infradead.org, jgross@suse.com, ravi.v.shankar@intel.com, mhiramat@kernel.org, andrew.cooper3@citrix.com, jiangshanlai@gmail.com, nik.borisov@suse.com Subject: [PATCH v12 32/37] x86/entry/calling: Allow PUSH_AND_CLEAR_REGS being used beyond actual entry code Date: Mon, 2 Oct 2023 23:24:53 -0700 Message-Id: <20231003062458.23552-33-xin3.li@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231003062458.23552-1-xin3.li@intel.com> References: <20231003062458.23552-1-xin3.li@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: "Peter Zijlstra (Intel)" PUSH_AND_CLEAR_REGS could be used besides actual entry code; in that case %rbp shouldn't be cleared (otherwise the frame pointer is destroyed) and UNWIND_HINT shouldn't be added. Signed-off-by: Peter Zijlstra (Intel) Tested-by: Shan Kang Signed-off-by: Xin Li --- arch/x86/entry/calling.h | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) diff --git a/arch/x86/entry/calling.h b/arch/x86/entry/calling.h index f6907627172b..eb57c023d5df 100644 --- a/arch/x86/entry/calling.h +++ b/arch/x86/entry/calling.h @@ -65,7 +65,7 @@ For 32-bit we have the following conventions - kernel is built with * for assembly code: */ -.macro PUSH_REGS rdx=%rdx rcx=%rcx rax=%rax save_ret=0 +.macro PUSH_REGS rdx=%rdx rcx=%rcx rax=%rax save_ret=0 unwind_hint=1 .if \save_ret pushq %rsi /* pt_regs->si */ movq 8(%rsp), %rsi /* temporarily store the return address in %rsi */ @@ -87,14 +87,17 @@ For 32-bit we have the following conventions - kernel is built with pushq %r13 /* pt_regs->r13 */ pushq %r14 /* pt_regs->r14 */ pushq %r15 /* pt_regs->r15 */ + + .if \unwind_hint UNWIND_HINT_REGS + .endif .if \save_ret pushq %rsi /* return address on top of stack */ .endif .endm -.macro CLEAR_REGS +.macro CLEAR_REGS clear_bp=1 /* * Sanitize registers of values that a speculation attack might * otherwise want to exploit. The lower registers are likely clobbered @@ -109,7 +112,9 @@ For 32-bit we have the following conventions - kernel is built with xorl %r10d, %r10d /* nospec r10 */ xorl %r11d, %r11d /* nospec r11 */ xorl %ebx, %ebx /* nospec rbx */ + .if \clear_bp xorl %ebp, %ebp /* nospec rbp */ + .endif xorl %r12d, %r12d /* nospec r12 */ xorl %r13d, %r13d /* nospec r13 */ xorl %r14d, %r14d /* nospec r14 */ @@ -117,9 +122,9 @@ For 32-bit we have the following conventions - kernel is built with .endm -.macro PUSH_AND_CLEAR_REGS rdx=%rdx rcx=%rcx rax=%rax save_ret=0 - PUSH_REGS rdx=\rdx, rcx=\rcx, rax=\rax, save_ret=\save_ret - CLEAR_REGS +.macro PUSH_AND_CLEAR_REGS rdx=%rdx rcx=%rcx rax=%rax save_ret=0 clear_bp=1 unwind_hint=1 + PUSH_REGS rdx=\rdx, rcx=\rcx, rax=\rax, save_ret=\save_ret unwind_hint=\unwind_hint + CLEAR_REGS clear_bp=\clear_bp .endm .macro POP_REGS pop_rdi=1 From patchwork Tue Oct 3 06:24:54 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Li, Xin3" X-Patchwork-Id: 13406858 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2D5B1E7542D for ; Tue, 3 Oct 2023 06:57:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239354AbjJCG5I (ORCPT ); Tue, 3 Oct 2023 02:57:08 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57170 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239370AbjJCG4g (ORCPT ); Tue, 3 Oct 2023 02:56:36 -0400 Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.126]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 053202722; Mon, 2 Oct 2023 23:55:46 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1696316147; x=1727852147; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=iqw0fwZbm5MXnC5p2WwXxWszbZfX0cXRwVyOWjiGl08=; b=nkJo6IUXVSfc8pPth6ieDgE7RSMF8GARKT4oy+ftKl3K0n0Dp0XjqEzE RarhANCwRXc//KmN0We4wvZK3ArRn1Zk+HPxkennMrlY4IsWEp7Way969 7ZJ337Lqb0qs0fGbvaio1dntS3nhBHV3dTZfURdiZohbwEafRCEY4L5lh wzgoLqRZLsvaQuKCz30P3r9+KiTEQwiBrUijLHkDwJMps6MYwlofCpknm 6tET5wQ6/SBPGsGWBMSztq4G1s0RmiDXX9CA8u/eioDbksv7TWDMrpI2q yBwF+VUZEg7HQnuclTsq/k111o/bshXozo1yCjRL532e5xp/BH+/bIvOe Q==; X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="367858328" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="367858328" Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Oct 2023 23:54:52 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="1081901008" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="1081901008" Received: from unknown (HELO fred..) ([172.25.112.68]) by fmsmga005.fm.intel.com with ESMTP; 02 Oct 2023 23:54:51 -0700 From: Xin Li To: linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-edac@vger.kernel.org, linux-hyperv@vger.kernel.org, kvm@vger.kernel.org, xen-devel@lists.xenproject.org Cc: tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, luto@kernel.org, pbonzini@redhat.com, seanjc@google.com, peterz@infradead.org, jgross@suse.com, ravi.v.shankar@intel.com, mhiramat@kernel.org, andrew.cooper3@citrix.com, jiangshanlai@gmail.com, nik.borisov@suse.com Subject: [PATCH v12 33/37] x86/entry: Add fred_entry_from_kvm() for VMX to handle IRQ/NMI Date: Mon, 2 Oct 2023 23:24:54 -0700 Message-Id: <20231003062458.23552-34-xin3.li@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231003062458.23552-1-xin3.li@intel.com> References: <20231003062458.23552-1-xin3.li@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org In IRQ/NMI induced VM exits, KVM VMX needs to execute the respective handlers, which requires the software to create a FRED stack frame, and use it to invoke the handlers. Add fred_irq_entry_from_kvm() for this job. Export fred_entry_from_kvm() because VMX can be compiled as a module. Suggested-by: Sean Christopherson Tested-by: Shan Kang Signed-off-by: Thomas Gleixner Signed-off-by: Xin Li --- Changes since v10: * Better explain the reason why no need to check current stack level (Paolo Bonzini). Changes since v9: * Shove the whole thing into arch/x86/entry/entry_64_fred.S for invoking external_interrupt() and fred_exc_nmi() (Sean Christopherson). * Correct and improve a few comments (Sean Christopherson). * Merge the two IRQ/NMI asm entries into one as it's fine to invoke noinstr code from regular code (Thomas Gleixner). * Setup the long mode and NMI flags in the augmented SS field of FRED stack frame in C instead of asm (Thomas Gleixner). * Add UNWIND_HINT_{SAVE,RESTORE} to get rid of the warning: "objtool: asm_fred_entry_from_kvm+0x0: unreachable instruction" (Peter Zijlstra). Changes since v8: * Add a new macro VMX_DO_FRED_EVENT_IRQOFF for FRED instead of refactoring VMX_DO_EVENT_IRQOFF (Sean Christopherson). * Do NOT use a trampoline, just LEA+PUSH the return RIP, PUSH the error code, and jump to the FRED kernel entry point for NMI or call external_interrupt() for IRQs (Sean Christopherson). * Call external_interrupt() only when FRED is enabled, and convert the non-FRED handling to external_interrupt() after FRED lands (Sean Christopherson). --- arch/x86/entry/entry_64_fred.S | 76 ++++++++++++++++++++++++++++++++++ arch/x86/entry/entry_fred.c | 14 +++++++ arch/x86/include/asm/fred.h | 18 ++++++++ 3 files changed, 108 insertions(+) diff --git a/arch/x86/entry/entry_64_fred.S b/arch/x86/entry/entry_64_fred.S index d1c2fc4af8ae..9917b4ea1543 100644 --- a/arch/x86/entry/entry_64_fred.S +++ b/arch/x86/entry/entry_64_fred.S @@ -4,7 +4,9 @@ */ #include +#include #include +#include #include "calling.h" @@ -54,3 +56,77 @@ SYM_CODE_START_NOALIGN(asm_fred_entrypoint_kernel) FRED_EXIT ERETS SYM_CODE_END(asm_fred_entrypoint_kernel) + +#if IS_ENABLED(CONFIG_KVM_INTEL) +SYM_FUNC_START(asm_fred_entry_from_kvm) + push %rbp + mov %rsp, %rbp + + UNWIND_HINT_SAVE + + /* + * Both IRQ and NMI from VMX can be handled on current task stack + * because there is no need to protect from reentrancy and the call + * stack leading to this helper is effectively constant and shallow + * (relatively speaking). Do the same when FRED is active, i.e., no + * need to check current stack level for a stack switch. + * + * Emulate the FRED-defined redzone and stack alignment. + */ + sub $(FRED_CONFIG_REDZONE_AMOUNT << 6), %rsp + and $FRED_STACK_FRAME_RSP_MASK, %rsp + + /* + * Start to push a FRED stack frame, which is always 64 bytes: + * + * +--------+-----------------+ + * | Bytes | Usage | + * +--------+-----------------+ + * | 63:56 | Reserved | + * | 55:48 | Event Data | + * | 47:40 | SS + Event Info | + * | 39:32 | RSP | + * | 31:24 | RFLAGS | + * | 23:16 | CS + Aux Info | + * | 15:8 | RIP | + * | 7:0 | Error Code | + * +--------+-----------------+ + */ + push $0 /* Reserved, must be 0 */ + push $0 /* Event data, 0 for IRQ/NMI */ + push %rdi /* fred_ss handed in by the caller */ + push %rbp + pushf + mov $__KERNEL_CS, %rax + push %rax + + /* + * Unlike the IDT event delivery, FRED _always_ pushes an error code + * after pushing the return RIP, thus the CALL instruction CANNOT be + * used here to push the return RIP, otherwise there is no chance to + * push an error code before invoking the IRQ/NMI handler. + * + * Use LEA to get the return RIP and push it, then push an error code. + */ + lea 1f(%rip), %rax + push %rax /* Return RIP */ + push $0 /* Error code, 0 for IRQ/NMI */ + + PUSH_AND_CLEAR_REGS clear_bp=0 unwind_hint=0 + movq %rsp, %rdi /* %rdi -> pt_regs */ + call __fred_entry_from_kvm /* Call the C entry point */ + POP_REGS + ERETS +1: + /* + * Objtool doesn't understand what ERETS does, this hint tells it that + * yes, we'll reach here and with what stack state. A save/restore pair + * isn't strictly needed, but it's the simplest form. + */ + UNWIND_HINT_RESTORE + pop %rbp + RET + +SYM_FUNC_END(asm_fred_entry_from_kvm) +EXPORT_SYMBOL_GPL(asm_fred_entry_from_kvm); +#endif diff --git a/arch/x86/entry/entry_fred.c b/arch/x86/entry/entry_fred.c index e80e3efbc057..3e33a4ab4624 100644 --- a/arch/x86/entry/entry_fred.c +++ b/arch/x86/entry/entry_fred.c @@ -242,3 +242,17 @@ __visible noinstr void fred_entry_from_kernel(struct pt_regs *regs) return fred_bad_type(regs, error_code); } } + +#if IS_ENABLED(CONFIG_KVM_INTEL) +__visible noinstr void __fred_entry_from_kvm(struct pt_regs *regs) +{ + switch (regs->fred_ss.type) { + case EVENT_TYPE_EXTINT: + return fred_extint(regs); + case EVENT_TYPE_NMI: + return fred_exc_nmi(regs); + default: + WARN_ON_ONCE(1); + } +} +#endif diff --git a/arch/x86/include/asm/fred.h b/arch/x86/include/asm/fred.h index 16a64ffecbf8..2fa9f34e5c95 100644 --- a/arch/x86/include/asm/fred.h +++ b/arch/x86/include/asm/fred.h @@ -9,6 +9,7 @@ #include #include +#include /* * FRED event return instruction opcodes for ERET{S,U}; supported in @@ -62,12 +63,29 @@ static __always_inline unsigned long fred_event_data(struct pt_regs *regs) void asm_fred_entrypoint_user(void); void asm_fred_entrypoint_kernel(void); +void asm_fred_entry_from_kvm(struct fred_ss); __visible void fred_entry_from_user(struct pt_regs *regs); __visible void fred_entry_from_kernel(struct pt_regs *regs); +__visible void __fred_entry_from_kvm(struct pt_regs *regs); + +/* Can be called from noinstr code, thus __always_inline */ +static __always_inline void fred_entry_from_kvm(unsigned int type, unsigned int vector) +{ + struct fred_ss ss = { + .ss =__KERNEL_DS, + .type = type, + .vector = vector, + .nmi = type == EVENT_TYPE_NMI, + .lm = 1, + }; + + asm_fred_entry_from_kvm(ss); +} #else /* CONFIG_X86_FRED */ static __always_inline unsigned long fred_event_data(struct pt_regs *regs) { return 0; } +static __always_inline void fred_entry_from_kvm(unsigned int type, unsigned int vector) { } #endif /* CONFIG_X86_FRED */ #endif /* !__ASSEMBLY__ */ From patchwork Tue Oct 3 06:24:55 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Li, Xin3" X-Patchwork-Id: 13406862 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4DB1FE7542F for ; Tue, 3 Oct 2023 06:57:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239531AbjJCG5x (ORCPT ); Tue, 3 Oct 2023 02:57:53 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57034 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239483AbjJCG5m (ORCPT ); Tue, 3 Oct 2023 02:57:42 -0400 Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.126]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 711952D4E; Mon, 2 Oct 2023 23:55:50 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1696316150; x=1727852150; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=MZgokrEaX/IcaX3hD6O7bYEAIXqVjdzkrr/jdEXzfh8=; b=RHKZ26EXYMUN1MmQGqLzHoujypNAdlxrzmTVLekI9NMyS/ON48W7bHtw 16IPD4Mv+c84/UJzDQwB0p3CW0yzq0g7BnAsxR4nCl3ZUvvdjX1XCKG0d jOztKVzwi7JwcJLTf0VF7wHxxPFGJXaYcMtQ0vbVr6UhGfJX7djI2huQZ 8dNA15SrN4vknkvijZGs0dNxg3cajJAprx5fM88jEnbKCTAMlmgDQ5Ov3 8toky2+eKeMB5WTC7umAf8nGDxvgA4LxzdN7/pzJryhDV16iECub7Vy2i 3sh/U2Pmuzs+ByEBSa0G/Mmxy81As9FyB05yZamDmIkyWz41CP3yxs+Kc w==; X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="367858329" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="367858329" Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Oct 2023 23:54:52 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="1081901012" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="1081901012" Received: from unknown (HELO fred..) ([172.25.112.68]) by fmsmga005.fm.intel.com with ESMTP; 02 Oct 2023 23:54:51 -0700 From: Xin Li To: linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-edac@vger.kernel.org, linux-hyperv@vger.kernel.org, kvm@vger.kernel.org, xen-devel@lists.xenproject.org Cc: tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, luto@kernel.org, pbonzini@redhat.com, seanjc@google.com, peterz@infradead.org, jgross@suse.com, ravi.v.shankar@intel.com, mhiramat@kernel.org, andrew.cooper3@citrix.com, jiangshanlai@gmail.com, nik.borisov@suse.com Subject: [PATCH v12 34/37] KVM: VMX: Call fred_entry_from_kvm() for IRQ/NMI handling Date: Mon, 2 Oct 2023 23:24:55 -0700 Message-Id: <20231003062458.23552-35-xin3.li@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231003062458.23552-1-xin3.li@intel.com> References: <20231003062458.23552-1-xin3.li@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org When FRED is enabled, call fred_entry_from_kvm() to handle IRQ/NMI in IRQ/NMI induced VM exits. Tested-by: Shan Kang Signed-off-by: Xin Li Acked-by: Paolo Bonzini --- arch/x86/kvm/vmx/vmx.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index 72e3943f3693..db55b8418fa3 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -38,6 +38,7 @@ #include #include #include +#include #include #include #include @@ -6962,14 +6963,16 @@ static void handle_external_interrupt_irqoff(struct kvm_vcpu *vcpu) { u32 intr_info = vmx_get_intr_info(vcpu); unsigned int vector = intr_info & INTR_INFO_VECTOR_MASK; - gate_desc *desc = (gate_desc *)host_idt_base + vector; if (KVM_BUG(!is_external_intr(intr_info), vcpu->kvm, "unexpected VM-Exit interrupt info: 0x%x", intr_info)) return; kvm_before_interrupt(vcpu, KVM_HANDLING_IRQ); - vmx_do_interrupt_irqoff(gate_offset(desc)); + if (cpu_feature_enabled(X86_FEATURE_FRED)) + fred_entry_from_kvm(EVENT_TYPE_EXTINT, vector); + else + vmx_do_interrupt_irqoff(gate_offset((gate_desc *)host_idt_base + vector)); kvm_after_interrupt(vcpu); vcpu->arch.at_instruction_boundary = true; @@ -7262,7 +7265,10 @@ static noinstr void vmx_vcpu_enter_exit(struct kvm_vcpu *vcpu, if ((u16)vmx->exit_reason.basic == EXIT_REASON_EXCEPTION_NMI && is_nmi(vmx_get_intr_info(vcpu))) { kvm_before_interrupt(vcpu, KVM_HANDLING_NMI); - vmx_do_nmi_irqoff(); + if (cpu_feature_enabled(X86_FEATURE_FRED)) + fred_entry_from_kvm(EVENT_TYPE_NMI, NMI_VECTOR); + else + vmx_do_nmi_irqoff(); kvm_after_interrupt(vcpu); } From patchwork Tue Oct 3 06:24:56 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Li, Xin3" X-Patchwork-Id: 13406865 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id E5C67E75430 for ; Tue, 3 Oct 2023 06:58:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239235AbjJCG65 (ORCPT ); Tue, 3 Oct 2023 02:58:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44850 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239485AbjJCG6m (ORCPT ); Tue, 3 Oct 2023 02:58:42 -0400 Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.126]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 69A2E2D4D; Mon, 2 Oct 2023 23:55:50 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1696316150; x=1727852150; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=KVAH30AJVp6O2e8FLYlwUzaPcwlh2ELK9dDq37AIdDs=; b=Z1LAqzi+Z3ye68zKOI2in3pIFKFY+Ay3dgi0OQrOWruDTJZoDjwpznfs N91WrtwrvnoRypg0vwvp1JFD8CjGAKv6xhQ/4y7u8Y2hrKDxNAK/hR7HH IOkNa0F13FTUIwYxHCxL45QrnTl3UtM8UC8A60bJwTQxu14i0aaeYAMm+ FmHM3gUN9V9NWWu7g1htpJzbBzg6nzS8suOkA0/9nz6WNFXtGsOF9kfJ5 ldjdyJEhSE+20+4JB6RTxLglKyiPpZ6leRrY+9zUvD+VU6PckhVpICGBY vHn74pxuUGt3FcZxt97J++g9GbmA+fT+2kkW06KZMVlPmQ1rvw0uVYz2D g==; X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="367858350" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="367858350" Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Oct 2023 23:54:53 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="1081901025" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="1081901025" Received: from unknown (HELO fred..) ([172.25.112.68]) by fmsmga005.fm.intel.com with ESMTP; 02 Oct 2023 23:54:52 -0700 From: Xin Li To: linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-edac@vger.kernel.org, linux-hyperv@vger.kernel.org, kvm@vger.kernel.org, xen-devel@lists.xenproject.org Cc: tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, luto@kernel.org, pbonzini@redhat.com, seanjc@google.com, peterz@infradead.org, jgross@suse.com, ravi.v.shankar@intel.com, mhiramat@kernel.org, andrew.cooper3@citrix.com, jiangshanlai@gmail.com, nik.borisov@suse.com Subject: [PATCH v12 35/37] x86/syscall: Split IDT syscall setup code into idt_syscall_init() Date: Mon, 2 Oct 2023 23:24:56 -0700 Message-Id: <20231003062458.23552-36-xin3.li@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231003062458.23552-1-xin3.li@intel.com> References: <20231003062458.23552-1-xin3.li@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Because FRED uses the ring 3 FRED entrypoint for SYSCALL and SYSENTER and ERETU is the only legit instruction to return to ring 3, there is NO need to setup SYSCALL and SYSENTER MSRs for FRED, except the IA32_STAR MSR. Split IDT syscall setup code into idt_syscall_init() to make it easy to skip syscall setup code when FRED is enabled. Suggested-by: Thomas Gleixner Tested-by: Shan Kang Signed-off-by: Xin Li --- arch/x86/kernel/cpu/common.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index 9b1cb6c938c4..69f9bdab19a9 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -2078,10 +2078,8 @@ static void wrmsrl_cstar(unsigned long val) wrmsrl(MSR_CSTAR, val); } -/* May not be marked __init: used by software suspend */ -void syscall_init(void) +static inline void idt_syscall_init(void) { - wrmsr(MSR_STAR, 0, (__USER32_CS << 16) | __KERNEL_CS); wrmsrl(MSR_LSTAR, (unsigned long)entry_SYSCALL_64); if (ia32_enabled()) { @@ -2115,6 +2113,15 @@ void syscall_init(void) X86_EFLAGS_AC|X86_EFLAGS_ID); } +/* May not be marked __init: used by software suspend */ +void syscall_init(void) +{ + /* The default user and kernel segments */ + wrmsr(MSR_STAR, 0, (__USER32_CS << 16) | __KERNEL_CS); + + idt_syscall_init(); +} + #else /* CONFIG_X86_64 */ #ifdef CONFIG_STACKPROTECTOR From patchwork Tue Oct 3 06:24:57 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Li, Xin3" X-Patchwork-Id: 13406859 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 71EA4E75432 for ; Tue, 3 Oct 2023 06:57:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239426AbjJCG5U (ORCPT ); Tue, 3 Oct 2023 02:57:20 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56802 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239505AbjJCG4v (ORCPT ); Tue, 3 Oct 2023 02:56:51 -0400 Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.126]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 889B72D60; Mon, 2 Oct 2023 23:55:51 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1696316152; x=1727852152; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=gVi2+XfvMsb0EmrgWxnOH1m9wi+KtBF4SipmwmPPA4A=; b=TRSU8OLXHxmX9JNeloNYVnTbE8smOxyd34t1GlwEoZw2VDGqKct6/sA6 cSrwmKVcj8JwYprzBclhHubQddJZ2kgQSBZCTjMCw/5cSc/KfaLgrH0tC KgGVIHjv/hmAPAUZTFLdJNVutLPq/IR0L9/diOcPlnASjrEjPq9gUHNrH REuD+EuEOQzDm/fb/oZqj8ulGdO5/zc3rwYoNJg/tmGvoGR4tAc9FKDgu g0mB2uMFctC+Mhipxq6PCa2RSNe7qlFUzVzwQplb8LRD5yaia0AE84zB9 mKoCai6WorTc+8xhbvuYk01AmY6axbsD/MOif3Zuq2aye71Nl2dF/OSfy Q==; X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="367858361" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="367858361" Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Oct 2023 23:54:53 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="1081901028" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="1081901028" Received: from unknown (HELO fred..) ([172.25.112.68]) by fmsmga005.fm.intel.com with ESMTP; 02 Oct 2023 23:54:52 -0700 From: Xin Li To: linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-edac@vger.kernel.org, linux-hyperv@vger.kernel.org, kvm@vger.kernel.org, xen-devel@lists.xenproject.org Cc: tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, luto@kernel.org, pbonzini@redhat.com, seanjc@google.com, peterz@infradead.org, jgross@suse.com, ravi.v.shankar@intel.com, mhiramat@kernel.org, andrew.cooper3@citrix.com, jiangshanlai@gmail.com, nik.borisov@suse.com Subject: [PATCH v12 36/37] x86/fred: Add FRED initialization functions Date: Mon, 2 Oct 2023 23:24:57 -0700 Message-Id: <20231003062458.23552-37-xin3.li@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231003062458.23552-1-xin3.li@intel.com> References: <20231003062458.23552-1-xin3.li@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: "H. Peter Anvin (Intel)" Add cpu_init_fred_exceptions() to: - Set FRED entrypoints for events happening in ring 0 and 3. - Specify the stack level for IRQs occurred ring 0. - Specify dedicated event stacks for #DB/NMI/#MCE/#DF. - Enable FRED and invalidtes IDT. - Force 32-bit system calls to use "int $0x80" only. Add fred_complete_exception_setup() to: - Initialize system_vectors as done for IDT systems. - Set unused sysvec_table entries to fred_handle_spurious_interrupt(). Signed-off-by: H. Peter Anvin (Intel) Co-developed-by: Xin Li Tested-by: Shan Kang Signed-off-by: Xin Li --- Changes since v9: * Set unused sysvec table entries to fred_handle_spurious_interrupt() in fred_complete_exception_setup() (Thomas Gleixner). Changes since v5: * Add a comment for FRED stack level settings (Lai Jiangshan). * Define NMI/#DB/#MCE/#DF stack levels using macros. --- arch/x86/entry/entry_fred.c | 21 +++++++++++++ arch/x86/include/asm/fred.h | 5 ++++ arch/x86/kernel/Makefile | 1 + arch/x86/kernel/fred.c | 59 +++++++++++++++++++++++++++++++++++++ 4 files changed, 86 insertions(+) create mode 100644 arch/x86/kernel/fred.c diff --git a/arch/x86/entry/entry_fred.c b/arch/x86/entry/entry_fred.c index 3e33a4ab4624..abe66d65fa2d 100644 --- a/arch/x86/entry/entry_fred.c +++ b/arch/x86/entry/entry_fred.c @@ -140,6 +140,27 @@ void __init fred_install_sysvec(unsigned int sysvec, idtentry_t handler) sysvec_table[sysvec - FIRST_SYSTEM_VECTOR] = handler; } +static noinstr void fred_handle_spurious_interrupt(struct pt_regs *regs) +{ + spurious_interrupt(regs, regs->fred_ss.vector); +} + +void __init fred_complete_exception_setup(void) +{ + unsigned int vector; + + for (vector = 0; vector < FIRST_EXTERNAL_VECTOR; vector++) + set_bit(vector, system_vectors); + + for (vector = 0; vector < NR_SYSTEM_VECTORS; vector++) { + if (sysvec_table[vector]) + set_bit(vector + FIRST_SYSTEM_VECTOR, system_vectors); + else + sysvec_table[vector] = fred_handle_spurious_interrupt; + } + fred_setup_done = true; +} + static noinstr void fred_extint(struct pt_regs *regs) { unsigned int vector = regs->fred_ss.vector; diff --git a/arch/x86/include/asm/fred.h b/arch/x86/include/asm/fred.h index 2fa9f34e5c95..e86c7ba32435 100644 --- a/arch/x86/include/asm/fred.h +++ b/arch/x86/include/asm/fred.h @@ -83,8 +83,13 @@ static __always_inline void fred_entry_from_kvm(unsigned int type, unsigned int asm_fred_entry_from_kvm(ss); } +void cpu_init_fred_exceptions(void); +void fred_complete_exception_setup(void); + #else /* CONFIG_X86_FRED */ static __always_inline unsigned long fred_event_data(struct pt_regs *regs) { return 0; } +static inline void cpu_init_fred_exceptions(void) { } +static inline void fred_complete_exception_setup(void) { } static __always_inline void fred_entry_from_kvm(unsigned int type, unsigned int vector) { } #endif /* CONFIG_X86_FRED */ #endif /* !__ASSEMBLY__ */ diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile index 3269a0e23d3a..8dfdae4111bb 100644 --- a/arch/x86/kernel/Makefile +++ b/arch/x86/kernel/Makefile @@ -47,6 +47,7 @@ obj-y += platform-quirks.o obj-y += process_$(BITS).o signal.o signal_$(BITS).o obj-y += traps.o idt.o irq.o irq_$(BITS).o dumpstack_$(BITS).o obj-y += time.o ioport.o dumpstack.o nmi.o +obj-$(CONFIG_X86_FRED) += fred.o obj-$(CONFIG_MODIFY_LDT_SYSCALL) += ldt.o obj-$(CONFIG_X86_KERNEL_IBT) += ibt_selftest.o obj-y += setup.o x86_init.o i8259.o irqinit.o diff --git a/arch/x86/kernel/fred.c b/arch/x86/kernel/fred.c new file mode 100644 index 000000000000..4bcd8791ad96 --- /dev/null +++ b/arch/x86/kernel/fred.c @@ -0,0 +1,59 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#include + +#include +#include +#include +#include + +/* #DB in the kernel would imply the use of a kernel debugger. */ +#define FRED_DB_STACK_LEVEL 1UL +#define FRED_NMI_STACK_LEVEL 2UL +#define FRED_MC_STACK_LEVEL 2UL +/* + * #DF is the highest level because a #DF means "something went wrong + * *while delivering an exception*." The number of cases for which that + * can happen with FRED is drastically reduced and basically amounts to + * "the stack you pointed me to is broken." Thus, always change stacks + * on #DF, which means it should be at the highest level. + */ +#define FRED_DF_STACK_LEVEL 3UL + +#define FRED_STKLVL(vector, lvl) ((lvl) << (2 * (vector))) + +void cpu_init_fred_exceptions(void) +{ + /* When FRED is enabled by default, remove this log message */ + pr_info("Initialize FRED on CPU%d\n", smp_processor_id()); + + wrmsrl(MSR_IA32_FRED_CONFIG, + /* Reserve for CALL emulation */ + FRED_CONFIG_REDZONE | + FRED_CONFIG_INT_STKLVL(0) | + FRED_CONFIG_ENTRYPOINT(asm_fred_entrypoint_user)); + + /* + * The purpose of separate stacks for NMI, #DB and #MC *in the kernel* + * (remember that user space faults are always taken on stack level 0) + * is to avoid overflowing the kernel stack. + */ + wrmsrl(MSR_IA32_FRED_STKLVLS, + FRED_STKLVL(X86_TRAP_DB, FRED_DB_STACK_LEVEL) | + FRED_STKLVL(X86_TRAP_NMI, FRED_NMI_STACK_LEVEL) | + FRED_STKLVL(X86_TRAP_MC, FRED_MC_STACK_LEVEL) | + FRED_STKLVL(X86_TRAP_DF, FRED_DF_STACK_LEVEL)); + + /* The FRED equivalents to IST stacks... */ + wrmsrl(MSR_IA32_FRED_RSP1, __this_cpu_ist_top_va(DB)); + wrmsrl(MSR_IA32_FRED_RSP2, __this_cpu_ist_top_va(NMI)); + wrmsrl(MSR_IA32_FRED_RSP3, __this_cpu_ist_top_va(DF)); + + /* Enable FRED */ + cr4_set_bits(X86_CR4_FRED); + /* Any further IDT use is a bug */ + idt_invalidate(); + + /* Use int $0x80 for 32-bit system calls in FRED mode */ + setup_clear_cpu_cap(X86_FEATURE_SYSENTER32); + setup_clear_cpu_cap(X86_FEATURE_SYSCALL32); +} From patchwork Tue Oct 3 06:24:58 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Li, Xin3" X-Patchwork-Id: 13406863 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 07ABFE7542F for ; Tue, 3 Oct 2023 06:58:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239436AbjJCG6t (ORCPT ); Tue, 3 Oct 2023 02:58:49 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45132 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239417AbjJCG6j (ORCPT ); Tue, 3 Oct 2023 02:58:39 -0400 Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.126]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8591B2D6B; Mon, 2 Oct 2023 23:55:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1696316153; x=1727852153; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=eEbBoWC5xFSRvZAlegSoACai1Gg5zcI498qdyjosTZg=; b=LCqK0SUNoVZuSlE87IrtuLL7LZs0+0Ox9Yhwsw7/VfVwP5gpiu4dgRI7 MKCqMvZ2UVJshQSQ9RVMH5Wl6Y0gAzJtD57YXbZ5coSKdQDnmyqXtmDr2 OYifj7m/SCRxt29TiduKgCbiw76TjCM4/sjG8Jjwb22ZzOXmlCrgaH3t0 5W2fMf+WBw1drmhtiilXDM7+M56dBG+gkpYunKTXL/PKucgUo1pZqgU9m PEsWB8y+wyMt7/ZFBeM+19oSOS/3+V0rnmKe9taBwlEwO/gBO0WEKcLnZ QCTHumOgDGnsbWX3RMY5jKT0V232HgOwZQmpkfsZxiWZHHABUAftFp0ru w==; X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="367858374" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="367858374" Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Oct 2023 23:54:54 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="1081901031" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="1081901031" Received: from unknown (HELO fred..) ([172.25.112.68]) by fmsmga005.fm.intel.com with ESMTP; 02 Oct 2023 23:54:53 -0700 From: Xin Li To: linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-edac@vger.kernel.org, linux-hyperv@vger.kernel.org, kvm@vger.kernel.org, xen-devel@lists.xenproject.org Cc: tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, luto@kernel.org, pbonzini@redhat.com, seanjc@google.com, peterz@infradead.org, jgross@suse.com, ravi.v.shankar@intel.com, mhiramat@kernel.org, andrew.cooper3@citrix.com, jiangshanlai@gmail.com, nik.borisov@suse.com Subject: [PATCH v12 37/37] x86/fred: Invoke FRED initialization code to enable FRED Date: Mon, 2 Oct 2023 23:24:58 -0700 Message-Id: <20231003062458.23552-38-xin3.li@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231003062458.23552-1-xin3.li@intel.com> References: <20231003062458.23552-1-xin3.li@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: "H. Peter Anvin (Intel)" Let cpu_init_exception_handling() call cpu_init_fred_exceptions() to initialize FRED. However if FRED is unavailable or disabled, it falls back to set up TSS IST and initialize IDT. Signed-off-by: H. Peter Anvin (Intel) Co-developed-by: Xin Li Tested-by: Shan Kang Signed-off-by: Xin Li --- Changes since v10: * No need to invalidate SYSCALL and SYSENTER MSRs (Thomas Gleixner). Changes since v8: * Move this patch after all required changes are in place (Thomas Gleixner). --- arch/x86/kernel/cpu/common.c | 22 +++++++++++++++++----- arch/x86/kernel/irqinit.c | 7 ++++++- arch/x86/kernel/traps.c | 5 ++++- 3 files changed, 27 insertions(+), 7 deletions(-) diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index 69f9bdab19a9..b103cfad0520 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -61,6 +61,7 @@ #include #include #include +#include #include #include #include @@ -2119,7 +2120,15 @@ void syscall_init(void) /* The default user and kernel segments */ wrmsr(MSR_STAR, 0, (__USER32_CS << 16) | __KERNEL_CS); - idt_syscall_init(); + /* + * Except the IA32_STAR MSR, there is NO need to setup SYSCALL and + * SYSENTER MSRs for FRED, because FRED uses the ring 3 FRED + * entrypoint for SYSCALL and SYSENTER, and ERETU is the only legit + * instruction to return to ring 3 (both sysexit and sysret cause + * #UD when FRED is enabled). + */ + if (!cpu_feature_enabled(X86_FEATURE_FRED)) + idt_syscall_init(); } #else /* CONFIG_X86_64 */ @@ -2235,8 +2244,9 @@ void cpu_init_exception_handling(void) /* paranoid_entry() gets the CPU number from the GDT */ setup_getcpu(cpu); - /* IST vectors need TSS to be set up. */ - tss_setup_ist(tss); + /* For IDT mode, IST vectors need to be set in TSS. */ + if (!cpu_feature_enabled(X86_FEATURE_FRED)) + tss_setup_ist(tss); tss_setup_io_bitmap(tss); set_tss_desc(cpu, &get_cpu_entry_area(cpu)->tss.x86_tss); @@ -2245,8 +2255,10 @@ void cpu_init_exception_handling(void) /* GHCB needs to be setup to handle #VC. */ setup_ghcb(); - /* Finally load the IDT */ - load_current_idt(); + if (cpu_feature_enabled(X86_FEATURE_FRED)) + cpu_init_fred_exceptions(); + else + load_current_idt(); } /* diff --git a/arch/x86/kernel/irqinit.c b/arch/x86/kernel/irqinit.c index c683666876f1..f79c5edc0b89 100644 --- a/arch/x86/kernel/irqinit.c +++ b/arch/x86/kernel/irqinit.c @@ -28,6 +28,7 @@ #include #include #include +#include #include /* @@ -96,7 +97,11 @@ void __init native_init_IRQ(void) /* Execute any quirks before the call gates are initialised: */ x86_init.irqs.pre_vector_init(); - idt_setup_apic_and_irq_gates(); + if (cpu_feature_enabled(X86_FEATURE_FRED)) + fred_complete_exception_setup(); + else + idt_setup_apic_and_irq_gates(); + lapic_assign_system_vectors(); if (!acpi_ioapic && !of_ioapic && nr_legacy_irqs()) { diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c index 848c85208a57..0ee78a30e14a 100644 --- a/arch/x86/kernel/traps.c +++ b/arch/x86/kernel/traps.c @@ -1411,7 +1411,10 @@ void __init trap_init(void) /* Initialize TSS before setting up traps so ISTs work */ cpu_init_exception_handling(); + /* Setup traps as cpu_init() might #GP */ - idt_setup_traps(); + if (!cpu_feature_enabled(X86_FEATURE_FRED)) + idt_setup_traps(); + cpu_init(); }