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-rw-r--r--arch/x86/include/asm/i387.h19
-rw-r--r--arch/x86/kernel/process_64.c5
-rw-r--r--arch/x86/kernel/traps.c14
3 files changed, 16 insertions, 22 deletions
diff --git a/arch/x86/include/asm/i387.h b/arch/x86/include/asm/i387.h
index 86974c72d0d0..01b115d86770 100644
--- a/arch/x86/include/asm/i387.h
+++ b/arch/x86/include/asm/i387.h
@@ -211,15 +211,6 @@ static inline void fpu_fxsave(struct fpu *fpu)
#endif /* CONFIG_X86_64 */
-/* We need a safe address that is cheap to find and that is already
- in L1 during context switch. The best choices are unfortunately
- different for UP and SMP */
-#ifdef CONFIG_SMP
-#define safe_address (__per_cpu_offset[0])
-#else
-#define safe_address (__get_cpu_var(kernel_cpustat).cpustat[CPUTIME_USER])
-#endif
-
/*
* These must be called with preempt disabled
*/
@@ -243,16 +234,6 @@ static inline void fpu_save_init(struct fpu *fpu)
if (unlikely(fpu->state->fxsave.swd & X87_FSW_ES))
asm volatile("fnclex");
-
- /* AMD K7/K8 CPUs don't save/restore FDP/FIP/FOP unless an exception
- is pending. Clear the x87 state here by setting it to fixed
- values. safe_address is a random variable that should be in L1 */
- alternative_input(
- ASM_NOP8 ASM_NOP2,
- "emms\n\t" /* clear stack tags */
- "fildl %P[addr]", /* set F?P to defined value */
- X86_FEATURE_FXSAVE_LEAK,
- [addr] "m" (safe_address));
}
static inline void __save_init_fpu(struct task_struct *tsk)
diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c
index 992b4e542bc3..753e803f7197 100644
--- a/arch/x86/kernel/process_64.c
+++ b/arch/x86/kernel/process_64.c
@@ -387,6 +387,8 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p)
struct tss_struct *tss = &per_cpu(init_tss, cpu);
unsigned fsindex, gsindex;
+ __unlazy_fpu(prev_p);
+
/*
* Reload esp0, LDT and the page table pointer:
*/
@@ -415,9 +417,6 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p)
load_TLS(next, cpu);
- /* Must be after DS reload */
- __unlazy_fpu(prev_p);
-
/*
* Leave lazy mode, flushing any hypercalls made here.
* This must be done before restoring TLS segments so
diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c
index 5afe824c66e5..4d42300dcd2c 100644
--- a/arch/x86/kernel/traps.c
+++ b/arch/x86/kernel/traps.c
@@ -585,6 +585,10 @@ void math_state_restore(void)
struct thread_info *thread = current_thread_info();
struct task_struct *tsk = thread->task;
+ /* We need a safe address that is cheap to find and that is already
+ in L1. We just brought in "thread->task", so use that */
+#define safe_address (thread->task)
+
if (!tsk_used_math(tsk)) {
local_irq_enable();
/*
@@ -602,6 +606,16 @@ void math_state_restore(void)
__thread_fpu_begin(thread);
+ /* AMD K7/K8 CPUs don't save/restore FDP/FIP/FOP unless an exception
+ is pending. Clear the x87 state here by setting it to fixed
+ values. safe_address is a random variable that should be in L1 */
+ alternative_input(
+ ASM_NOP8 ASM_NOP2,
+ "emms\n\t" /* clear stack tags */
+ "fildl %P[addr]", /* set F?P to defined value */
+ X86_FEATURE_FXSAVE_LEAK,
+ [addr] "m" (safe_address));
+
/*
* Paranoid restore. send a SIGSEGV if we fail to restore the state.
*/