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| author | Andy Lutomirski <luto@kernel.org> | 2017-11-02 08:59:10 +0100 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2017-11-02 11:04:44 +0100 |
| commit | da51da189a24bb9b7e2d5a123be096e51a4695a5 (patch) | |
| tree | 39b88e6bed96687f02eabe22ed211f7bc78c9c0b /arch/x86/kernel/vm86_32.c | |
| parent | x86/entry/32: Pull the MSR_IA32_SYSENTER_CS update code out of native_load_sp0() (diff) | |
| download | linux-da51da189a24bb9b7e2d5a123be096e51a4695a5.tar.xz linux-da51da189a24bb9b7e2d5a123be096e51a4695a5.zip | |
x86/entry/64: Pass SP0 directly to load_sp0()
load_sp0() had an odd signature:
void load_sp0(struct tss_struct *tss, struct thread_struct *thread);
Simplify it to:
void load_sp0(unsigned long sp0);
Also simplify a few get_cpu()/put_cpu() sequences to
preempt_disable()/preempt_enable().
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: Borislav Petkov <bpetkov@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/2655d8b42ed940aa384fe18ee1129bbbcf730a08.1509609304.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/kernel/vm86_32.c')
| -rw-r--r-- | arch/x86/kernel/vm86_32.c | 14 |
1 files changed, 6 insertions, 8 deletions
diff --git a/arch/x86/kernel/vm86_32.c b/arch/x86/kernel/vm86_32.c index 5bc1c3ab6287..0f1d92cd20ad 100644 --- a/arch/x86/kernel/vm86_32.c +++ b/arch/x86/kernel/vm86_32.c @@ -94,7 +94,6 @@ void save_v86_state(struct kernel_vm86_regs *regs, int retval) { - struct tss_struct *tss; struct task_struct *tsk = current; struct vm86plus_struct __user *user; struct vm86 *vm86 = current->thread.vm86; @@ -146,13 +145,13 @@ void save_v86_state(struct kernel_vm86_regs *regs, int retval) do_exit(SIGSEGV); } - tss = &per_cpu(cpu_tss, get_cpu()); + preempt_disable(); tsk->thread.sp0 = vm86->saved_sp0; tsk->thread.sysenter_cs = __KERNEL_CS; - load_sp0(tss, &tsk->thread); + load_sp0(tsk->thread.sp0); refresh_sysenter_cs(&tsk->thread); vm86->saved_sp0 = 0; - put_cpu(); + preempt_enable(); memcpy(®s->pt, &vm86->regs32, sizeof(struct pt_regs)); @@ -238,7 +237,6 @@ SYSCALL_DEFINE2(vm86, unsigned long, cmd, unsigned long, arg) static long do_sys_vm86(struct vm86plus_struct __user *user_vm86, bool plus) { - struct tss_struct *tss; struct task_struct *tsk = current; struct vm86 *vm86 = tsk->thread.vm86; struct kernel_vm86_regs vm86regs; @@ -366,8 +364,8 @@ static long do_sys_vm86(struct vm86plus_struct __user *user_vm86, bool plus) vm86->saved_sp0 = tsk->thread.sp0; lazy_save_gs(vm86->regs32.gs); - tss = &per_cpu(cpu_tss, get_cpu()); /* make room for real-mode segments */ + preempt_disable(); tsk->thread.sp0 += 16; if (static_cpu_has(X86_FEATURE_SEP)) { @@ -375,8 +373,8 @@ static long do_sys_vm86(struct vm86plus_struct __user *user_vm86, bool plus) refresh_sysenter_cs(&tsk->thread); } - load_sp0(tss, &tsk->thread); - put_cpu(); + load_sp0(tsk->thread.sp0); + preempt_enable(); if (vm86->flags & VM86_SCREEN_BITMAP) mark_screen_rdonly(tsk->mm); |