From 51115d4d45700fc7c08306f7ba6e68551f526ae5 Mon Sep 17 00:00:00 2001 From: Brian Gerst Date: Fri, 3 Sep 2010 21:17:10 -0400 Subject: [PATCH] x86, fpu: Merge tolerant_fwait() Commit e2e75c91 merged the math exception handler, allowing both 32-bit and 64-bit to handle math exceptions from kernel mode. Switch to using the 64-bit version of tolerant_fwait() without fnclex, which simply ignores the exception if one is still pending from userspace. Signed-off-by: Brian Gerst Acked-by: Pekka Enberg Cc: Suresh Siddha LKML-Reference: <1283563039-3466-4-git-send-email-brgerst@gmail.com> Signed-off-by: H. Peter Anvin --- arch/x86/include/asm/i387.h | 19 ++++--------------- 1 file changed, 4 insertions(+), 15 deletions(-) diff --git a/arch/x86/include/asm/i387.h b/arch/x86/include/asm/i387.h index a73a8d5a5e69..5d8f9a79fa5d 100644 --- a/arch/x86/include/asm/i387.h +++ b/arch/x86/include/asm/i387.h @@ -77,15 +77,6 @@ static inline void sanitize_i387_state(struct task_struct *tsk) } #ifdef CONFIG_X86_64 - -/* Ignore delayed exceptions from user space */ -static inline void tolerant_fwait(void) -{ - asm volatile("1: fwait\n" - "2:\n" - _ASM_EXTABLE(1b, 2b)); -} - static inline int fxrstor_checking(struct i387_fxsave_struct *fx) { int err; @@ -220,11 +211,6 @@ extern void finit_soft_fpu(struct i387_soft_struct *soft); static inline void finit_soft_fpu(struct i387_soft_struct *soft) {} #endif -static inline void tolerant_fwait(void) -{ - asm volatile("fnclex ; fwait"); -} - /* perform fxrstor iff the processor has extended states, otherwise frstor */ static inline int fxrstor_checking(struct i387_fxsave_struct *fx) { @@ -344,7 +330,10 @@ static inline void __unlazy_fpu(struct task_struct *tsk) static inline void __clear_fpu(struct task_struct *tsk) { if (task_thread_info(tsk)->status & TS_USEDFPU) { - tolerant_fwait(); + /* Ignore delayed exceptions from user space */ + asm volatile("1: fwait\n" + "2:\n" + _ASM_EXTABLE(1b, 2b)); task_thread_info(tsk)->status &= ~TS_USEDFPU; stts(); } -- 2.34.1