From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755523AbdKBLAK (ORCPT ); Thu, 2 Nov 2017 07:00:10 -0400 Received: from terminus.zytor.com ([65.50.211.136]:42229 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752352AbdKBLAJ (ORCPT ); Thu, 2 Nov 2017 07:00:09 -0400 Date: Thu, 2 Nov 2017 03:55:36 -0700 From: tip-bot for Andy Lutomirski Message-ID: Cc: mingo@kernel.org, dave.hansen@intel.com, hpa@zytor.com, brgerst@gmail.com, tglx@linutronix.de, bpetkov@suse.de, linux-kernel@vger.kernel.org, torvalds@linux-foundation.org, luto@kernel.org, peterz@infradead.org, bp@suse.de Reply-To: luto@kernel.org, bp@suse.de, peterz@infradead.org, torvalds@linux-foundation.org, linux-kernel@vger.kernel.org, tglx@linutronix.de, bpetkov@suse.de, dave.hansen@intel.com, brgerst@gmail.com, hpa@zytor.com, mingo@kernel.org In-Reply-To: <2d231687f4ff288c9d9e98d7861b7df374246ac3.1509609304.git.luto@kernel.org> References: <2d231687f4ff288c9d9e98d7861b7df374246ac3.1509609304.git.luto@kernel.org> To: linux-tip-commits@vger.kernel.org Subject: [tip:x86/asm] x86/entry/64: Remove all remaining direct thread_struct::sp0 reads Git-Commit-ID: 46f5a10a721ce8dce8cc8fe55279b49e1c6b3288 X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: 46f5a10a721ce8dce8cc8fe55279b49e1c6b3288 Gitweb: https://git.kernel.org/tip/46f5a10a721ce8dce8cc8fe55279b49e1c6b3288 Author: Andy Lutomirski AuthorDate: Thu, 2 Nov 2017 00:59:14 -0700 Committer: Ingo Molnar CommitDate: Thu, 2 Nov 2017 11:04:47 +0100 x86/entry/64: Remove all remaining direct thread_struct::sp0 reads The only remaining readers in context switch code or vm86(), and they all just want to update TSS.sp0 to match the current task. Replace them all with a new helper update_sp0(). Signed-off-by: Andy Lutomirski Reviewed-by: Borislav Petkov Cc: Borislav Petkov Cc: Brian Gerst Cc: Dave Hansen Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/2d231687f4ff288c9d9e98d7861b7df374246ac3.1509609304.git.luto@kernel.org Signed-off-by: Ingo Molnar --- arch/x86/include/asm/switch_to.h | 6 ++++++ arch/x86/kernel/process_32.c | 2 +- arch/x86/kernel/process_64.c | 2 +- arch/x86/kernel/vm86_32.c | 4 ++-- 4 files changed, 10 insertions(+), 4 deletions(-) diff --git a/arch/x86/include/asm/switch_to.h b/arch/x86/include/asm/switch_to.h index 7ae8caf..54e64d9 100644 --- a/arch/x86/include/asm/switch_to.h +++ b/arch/x86/include/asm/switch_to.h @@ -84,4 +84,10 @@ static inline void refresh_sysenter_cs(struct thread_struct *thread) } #endif +/* This is used when switching tasks or entering/exiting vm86 mode. */ +static inline void update_sp0(struct task_struct *task) +{ + load_sp0(task->thread.sp0); +} + #endif /* _ASM_X86_SWITCH_TO_H */ diff --git a/arch/x86/kernel/process_32.c b/arch/x86/kernel/process_32.c index 40b8587..45bf0c5 100644 --- a/arch/x86/kernel/process_32.c +++ b/arch/x86/kernel/process_32.c @@ -287,7 +287,7 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p) * current_thread_info(). Refresh the SYSENTER configuration in * case prev or next is vm86. */ - load_sp0(next->sp0); + update_sp0(next_p); refresh_sysenter_cs(next); this_cpu_write(cpu_current_top_of_stack, (unsigned long)task_stack_page(next_p) + diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c index 2124304..45e3809 100644 --- a/arch/x86/kernel/process_64.c +++ b/arch/x86/kernel/process_64.c @@ -465,7 +465,7 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p) this_cpu_write(current_task, next_p); /* Reload sp0. */ - load_sp0(next->sp0); + update_sp0(next_p); /* * Now maybe reload the debug registers and handle I/O bitmaps diff --git a/arch/x86/kernel/vm86_32.c b/arch/x86/kernel/vm86_32.c index 0f1d92c..a7b44c7 100644 --- a/arch/x86/kernel/vm86_32.c +++ b/arch/x86/kernel/vm86_32.c @@ -148,7 +148,7 @@ void save_v86_state(struct kernel_vm86_regs *regs, int retval) preempt_disable(); tsk->thread.sp0 = vm86->saved_sp0; tsk->thread.sysenter_cs = __KERNEL_CS; - load_sp0(tsk->thread.sp0); + update_sp0(tsk); refresh_sysenter_cs(&tsk->thread); vm86->saved_sp0 = 0; preempt_enable(); @@ -373,7 +373,7 @@ static long do_sys_vm86(struct vm86plus_struct __user *user_vm86, bool plus) refresh_sysenter_cs(&tsk->thread); } - load_sp0(tsk->thread.sp0); + update_sp0(tsk); preempt_enable(); if (vm86->flags & VM86_SCREEN_BITMAP)