diff options
Diffstat (limited to 'arch/x86/include/asm/fpu')
| -rw-r--r-- | arch/x86/include/asm/fpu/api.h | 15 | ||||
| -rw-r--r-- | arch/x86/include/asm/fpu/internal.h | 5 |
2 files changed, 9 insertions, 11 deletions
diff --git a/arch/x86/include/asm/fpu/api.h b/arch/x86/include/asm/fpu/api.h index a9caac9d4a72..b56d504af654 100644 --- a/arch/x86/include/asm/fpu/api.h +++ b/arch/x86/include/asm/fpu/api.h @@ -12,17 +12,12 @@ #define _ASM_X86_FPU_API_H /* - * Careful: __kernel_fpu_begin/end() must be called with preempt disabled - * and they don't touch the preempt state on their own. - * If you enable preemption after __kernel_fpu_begin(), preempt notifier - * should call the __kernel_fpu_end() to prevent the kernel/user FPU - * state from getting corrupted. KVM for example uses this model. - * - * All other cases use kernel_fpu_begin/end() which disable preemption - * during kernel FPU usage. + * Use kernel_fpu_begin/end() if you intend to use FPU in kernel context. It + * disables preemption so be careful if you intend to use it for long periods + * of time. + * If you intend to use the FPU in softirq you need to check first with + * irq_fpu_usable() if it is possible. */ -extern void __kernel_fpu_begin(void); -extern void __kernel_fpu_end(void); extern void kernel_fpu_begin(void); extern void kernel_fpu_end(void); extern bool irq_fpu_usable(void); diff --git a/arch/x86/include/asm/fpu/internal.h b/arch/x86/include/asm/fpu/internal.h index 5f7290e6e954..fa2c93cb42a2 100644 --- a/arch/x86/include/asm/fpu/internal.h +++ b/arch/x86/include/asm/fpu/internal.h @@ -106,6 +106,9 @@ extern void fpstate_sanitize_xstate(struct fpu *fpu); #define user_insn(insn, output, input...) \ ({ \ int err; \ + \ + might_fault(); \ + \ asm volatile(ASM_STAC "\n" \ "1:" #insn "\n\t" \ "2: " ASM_CLAC "\n" \ @@ -226,7 +229,7 @@ static inline void copy_fxregs_to_kernel(struct fpu *fpu) "3: movl $-2,%[err]\n\t" \ "jmp 2b\n\t" \ ".popsection\n\t" \ - _ASM_EXTABLE_UA(1b, 3b) \ + _ASM_EXTABLE(1b, 3b) \ : [err] "=r" (err) \ : "D" (st), "m" (*st), "a" (lmask), "d" (hmask) \ : "memory") |