From patchwork Thu Feb 23 19:11:39 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Usama Arif X-Patchwork-Id: 13150689 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 20F61C636D7 for ; Thu, 23 Feb 2023 19:12:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232129AbjBWTM6 (ORCPT ); Thu, 23 Feb 2023 14:12:58 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60254 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232112AbjBWTMv (ORCPT ); Thu, 23 Feb 2023 14:12:51 -0500 Received: from mail-wr1-x42a.google.com (mail-wr1-x42a.google.com [IPv6:2a00:1450:4864:20::42a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1C1835D44A for ; Thu, 23 Feb 2023 11:12:28 -0800 (PST) Received: by mail-wr1-x42a.google.com with SMTP id bw19so928551wrb.13 for ; Thu, 23 Feb 2023 11:12:28 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance.com; s=google; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=Ef9SnPny8CPfpZmm6N0jiCHwpvy9x8nd/PRiLPI7xag=; b=XrQnR2cfEdgLwqJ0o6NE4oQo94jXmalIs45LryMzC+zupXpNrQFyQaJDH9RhoY4NO/ X/U5UAZk9WIGO8WHqPCfOQy+GntieRIMVjX2CQO+K+o5U5aUtGC7UKKBzKuMbm21D8lp u0cZi//QcFT5PIFqhoirDUIPE4UgvBV1nDVlTma2g2xOeU/86sFo7mb1nakDRvdHP19X b6Hy4TfrowFaRJqrFtRTUHv3cCDJZXsk3yJr4KG4iRmgLGfdgrVmlvq6hEmItm3DhhlW um39DZUjO4+pDqLuLxhSJqXCoyrzn21aC2w8ZXkjEK+FWBK2QkpLgcwgQVEbVKEkuKEt bN/Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=Ef9SnPny8CPfpZmm6N0jiCHwpvy9x8nd/PRiLPI7xag=; b=kNfZ/syJkWwuuYys5vQ8aj2OY5+C6HUhHEuw5nyMqzSi+bvVRRuBgALx1T2l8nubcc ZRIte5Oi189ckulTj1TqCXCXmXl2UL0jIqSQczNDkVCmMY4r62Jf9hHxELI1Ckylkys1 bOGZFpTR6Wwf++1PLMbt/bAN9l0C7ChkxF5MozH35tek4YYqOfvtE+q6QzLM3+XrZ8RL uYIjHJmE/QT8XoKLZoQCUThZ0sJYs26Y51R1dSQ0F6WBlL/uO/IJtmoLxg4usVfrTEKY ywolZC0NGAzCKiAzyS9hSsup/qMc0nkfbn/Qz4ZXO4RbRz9Zfa4orUtCewfXYLRwD2nz vwlw== X-Gm-Message-State: AO0yUKX4SSvMXlv1yNIACqAByBizN/vtxqCGd9IzkeLfNQjaBay4NfyA q/gc8u1oAu7lSW3UpkXBrnRRzw== X-Google-Smtp-Source: AK7set98tD0e8cEXZx0hdoDPqzv1pTcwpHGVhaE8HSWqaC4eiTYx1JWNklrl/RcXYo0eJXOCliLKFg== X-Received: by 2002:a5d:410b:0:b0:2c5:58f5:3c40 with SMTP id l11-20020a5d410b000000b002c558f53c40mr9571433wrp.47.1677179513058; Thu, 23 Feb 2023 11:11:53 -0800 (PST) Received: from usaari01.cust.communityfibre.co.uk ([2a02:6b6a:b566:0:5ee0:5af0:64bd:6198]) by smtp.gmail.com with ESMTPSA id b15-20020a5d4b8f000000b002c561805a4csm12957286wrt.45.2023.02.23.11.11.52 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 23 Feb 2023 11:11:52 -0800 (PST) From: Usama Arif To: dwmw2@infradead.org, tglx@linutronix.de, kim.phillips@amd.com, brgerst@gmail.com Cc: piotrgorski@cachyos.org, oleksandr@natalenko.name, arjan@linux.intel.com, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, hpa@zytor.com, x86@kernel.org, pbonzini@redhat.com, paulmck@kernel.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, rcu@vger.kernel.org, mimoja@mimoja.de, hewenliang4@huawei.com, thomas.lendacky@amd.com, seanjc@google.com, pmenzel@molgen.mpg.de, fam.zheng@bytedance.com, punit.agrawal@bytedance.com, simon.evans@bytedance.com, liangma@liangbit.com, David Woodhouse , Usama Arif Subject: [PATCH v11 11/12] x86/smpboot: Remove initial_gs Date: Thu, 23 Feb 2023 19:11:39 +0000 Message-Id: <20230223191140.4155012-12-usama.arif@bytedance.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20230223191140.4155012-1-usama.arif@bytedance.com> References: <20230223191140.4155012-1-usama.arif@bytedance.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Brian Gerst Use the percpu offset directly to set GSBASE. Signed-off-by: Brian Gerst Reviewed-by: David Woodhouse Signed-off-by: David Woodhouse Tested-by: Usama Arif Signed-off-by: Usama Arif --- arch/x86/include/asm/realmode.h | 1 - arch/x86/kernel/acpi/sleep.c | 1 - arch/x86/kernel/head_64.S | 34 ++++++++++----------------------- 3 files changed, 10 insertions(+), 26 deletions(-) diff --git a/arch/x86/include/asm/realmode.h b/arch/x86/include/asm/realmode.h index f0357cfe2fb0..87e5482acd0d 100644 --- a/arch/x86/include/asm/realmode.h +++ b/arch/x86/include/asm/realmode.h @@ -60,7 +60,6 @@ extern struct real_mode_header *real_mode_header; extern unsigned char real_mode_blob_end[]; extern unsigned long initial_code; -extern unsigned long initial_gs; extern unsigned long initial_stack; #ifdef CONFIG_AMD_MEM_ENCRYPT extern unsigned long initial_vc_handler; diff --git a/arch/x86/kernel/acpi/sleep.c b/arch/x86/kernel/acpi/sleep.c index 6538ddb55f28..214dd4a79860 100644 --- a/arch/x86/kernel/acpi/sleep.c +++ b/arch/x86/kernel/acpi/sleep.c @@ -114,7 +114,6 @@ int x86_acpi_suspend_lowlevel(void) #else /* CONFIG_64BIT */ #ifdef CONFIG_SMP current->thread.sp = (unsigned long)temp_stack + sizeof(temp_stack); - initial_gs = per_cpu_offset(smp_processor_id()); /* Force the startup into boot mode */ saved_smpboot_ctrl = xchg(&smpboot_control, 0); #endif diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S index 0dd57d573a0e..9ed87ba0609f 100644 --- a/arch/x86/kernel/head_64.S +++ b/arch/x86/kernel/head_64.S @@ -67,18 +67,10 @@ SYM_CODE_START_NOALIGN(startup_64) leaq _text(%rip), %rdi - /* - * initial_gs points to initial fixed_percpu_data struct with storage for - * the stack protector canary. Global pointer fixups are needed at this - * stage, so apply them as is done in fixup_pointer(), and initialize %gs - * such that the canary can be accessed at %gs:40 for subsequent C calls. - */ + /* Setup GSBASE to allow stack canary access for C code */ movl $MSR_GS_BASE, %ecx - movq initial_gs(%rip), %rax - movq $_text, %rdx - subq %rdx, %rax - addq %rdi, %rax - movq %rax, %rdx + leaq INIT_PER_CPU_VAR(fixed_percpu_data)(%rip), %rdx + movl %edx, %eax shrq $32, %rdx wrmsr @@ -243,10 +235,7 @@ SYM_INNER_LABEL(secondary_startup_64_no_verify, SYM_L_GLOBAL) ANNOTATE_NOENDBR // above #ifdef CONFIG_SMP - /* - * Is this the boot CPU coming up? If so everything is available - * in initial_gs. - */ + /* Is this the boot CPU coming up? */ movl smpboot_control(%rip), %edx testl $STARTUP_SECONDARY, %edx jz .Linit_cpu0_data @@ -308,12 +297,7 @@ SYM_INNER_LABEL(secondary_startup_64_no_verify, SYM_L_GLOBAL) .Linit_cpu_data: /* Get the per cpu offset for the given CPU# which is in ECX */ - leaq __per_cpu_offset(%rip), %rbx - movq (%rbx,%rcx,8), %rbx - /* Save it for GS BASE setup */ - movq %rbx, initial_gs(%rip) - - movq %rbx, %rdx + movq __per_cpu_offset(,%rcx,8), %rdx #else xorl %edx, %edx #endif /* CONFIG_SMP */ @@ -363,8 +347,11 @@ SYM_INNER_LABEL(secondary_startup_64_no_verify, SYM_L_GLOBAL) * the per cpu areas are set up. */ movl $MSR_GS_BASE,%ecx - movl initial_gs(%rip),%eax - movl initial_gs+4(%rip),%edx +#ifndef CONFIG_SMP + leaq INIT_PER_CPU_VAR(fixed_percpu_data)(%rip), %rdx +#endif + movl %edx, %eax + shrq $32, %rdx wrmsr /* Drop the realmode protection. For the boot CPU the pointer is NULL! */ @@ -514,7 +501,6 @@ SYM_CODE_END(vc_boot_ghcb) __REFDATA .balign 8 SYM_DATA(initial_code, .quad x86_64_start_kernel) -SYM_DATA(initial_gs, .quad INIT_PER_CPU_VAR(fixed_percpu_data)) #ifdef CONFIG_AMD_MEM_ENCRYPT SYM_DATA(initial_vc_handler, .quad handle_vc_boot_ghcb) #endif