From patchwork Sat Sep 23 09:41:54 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Li, Xin3" X-Patchwork-Id: 13396622 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 E2E10CE7A88 for ; Sat, 23 Sep 2023 10:12:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231693AbjIWKM2 (ORCPT ); Sat, 23 Sep 2023 06:12:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59026 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231444AbjIWKL4 (ORCPT ); Sat, 23 Sep 2023 06:11:56 -0400 Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.100]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A9ED91B2; Sat, 23 Sep 2023 03:11:46 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1695463906; x=1726999906; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=U5v5FfPZcbv+kEeu4BDXYc9n8fkslqM+14uJJDiLwkk=; b=ixQUNrJAyVY8HNPqmZmobN0KOm8z0sYCjmnxRgrHa21aF7gDb2l0JjAJ SduROhw4WqIZFzrJIDZikzmbl2ys2xAw1kINfl5W9KbYeaI1R2HdAkmiJ LfRlTvm8JCW7SUoZGZ1/uC6Ga0URrF/GBtxZPvJwJLwMCFuhK04I0QCz9 rK10C81fTG8soG4v2mXvLBzavgFbIlTNWqXfSE3Av6RF7QxSHNFK1f9aK FUGw2TIvFu1AY7OLsr/H2sye/yG32Ib0HAMQ4RCnkTQZuUfds8uhl1JSR coumZW0UTi/E9IgZwJ0gRcq6gwS8nB9WTXXQIN6INyHqDviyXCzl9yFGb w==; X-IronPort-AV: E=McAfee;i="6600,9927,10841"; a="447492302" X-IronPort-AV: E=Sophos;i="6.03,171,1694761200"; d="scan'208";a="447492302" Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 23 Sep 2023 03:11:45 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10841"; a="813388168" X-IronPort-AV: E=Sophos;i="6.03,171,1694761200"; d="scan'208";a="813388168" Received: from unknown (HELO fred..) ([172.25.112.68]) by fmsmga008.fm.intel.com with ESMTP; 23 Sep 2023 03:11:44 -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 v11 19/37] x86/fred: Update MSR_IA32_FRED_RSP0 during task switch Date: Sat, 23 Sep 2023 02:41:54 -0700 Message-Id: <20230923094212.26520-20-xin3.li@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230923094212.26520-1-xin3.li@intel.com> References: <20230923094212.26520-1-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 }