diff options
Diffstat (limited to 'arch/x86/kernel/traps.c')
| -rw-r--r-- | arch/x86/kernel/traps.c | 40 |
1 files changed, 8 insertions, 32 deletions
diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c index 77da5b475ad..4bbe04d9674 100644 --- a/arch/x86/kernel/traps.c +++ b/arch/x86/kernel/traps.c @@ -571,37 +571,6 @@ asmlinkage void __attribute__((weak)) smp_threshold_interrupt(void) } /* - * This gets called with the process already owning the - * FPU state, and with CR0.TS cleared. It just needs to - * restore the FPU register state. - */ -void __math_state_restore(struct task_struct *tsk) -{ - /* We need a safe address that is cheap to find and that is already - in L1. We've just brought in "tsk->thread.has_fpu", so use that */ -#define safe_address (tsk->thread.has_fpu) - - /* 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. - */ - if (unlikely(restore_fpu_checking(tsk))) { - __thread_fpu_end(tsk); - force_sig(SIGSEGV, tsk); - return; - } -} - -/* * 'math_state_restore()' saves the current math information in the * old math state array, and gets the new ones from the current task * @@ -631,7 +600,14 @@ void math_state_restore(void) } __thread_fpu_begin(tsk); - __math_state_restore(tsk); + /* + * Paranoid restore. send a SIGSEGV if we fail to restore the state. + */ + if (unlikely(restore_fpu_checking(tsk))) { + __thread_fpu_end(tsk); + force_sig(SIGSEGV, tsk); + return; + } tsk->fpu_counter++; } |