diff --git a/arch/x86/include/asm/fpu/internal.h b/arch/x86/include/asm/fpu/internal.h index 1dcb29e8d92c043cf7496c3439acfd69246ca971..590f27488fcaf68feb8b043264a46b6920606336 100644 --- a/arch/x86/include/asm/fpu/internal.h +++ b/arch/x86/include/asm/fpu/internal.h @@ -488,15 +488,16 @@ DECLARE_PER_CPU(struct fpu *, fpu_fpregs_owner_ctx); * * Any code that clobbers the FPU registers or updates the in-memory * FPU state for a task MUST let the rest of the kernel know that the - * FPU registers are no longer valid for this task. Calling either of - * these two invalidate functions is enough, use whichever is convenient. + * FPU registers are no longer valid for this task. * - * Must be run with preemption disabled: this clears the fpu_fpregs_owner_ctx, - * on this CPU. + * Either one of these invalidation functions is enough. Invalidate + * a resource you control: CPU if using the CPU for something else + * (with preemption disabled), FPU for the current task, or a task that + * is prevented from running by the current task. */ -static inline void __cpu_invalidate_fpregs_state(unsigned int cpu) +static inline void __cpu_invalidate_fpregs_state(void) { - per_cpu(fpu_fpregs_owner_ctx, cpu) = NULL; + __this_cpu_write(fpu_fpregs_owner_ctx, NULL); } static inline void __fpu_invalidate_fpregs_state(struct fpu *fpu) diff --git a/arch/x86/kernel/fpu/core.c b/arch/x86/kernel/fpu/core.c index 25a45ddfdbcf798f8e64c6e8774d6578beddb78a..30f11ab6c07e37fa53c52841062f7d6962b5ae85 100644 --- a/arch/x86/kernel/fpu/core.c +++ b/arch/x86/kernel/fpu/core.c @@ -106,7 +106,7 @@ void __kernel_fpu_begin(void) */ copy_fpregs_to_fpstate(fpu); } else { - this_cpu_write(fpu_fpregs_owner_ctx, NULL); + __cpu_invalidate_fpregs_state(); } } EXPORT_SYMBOL(__kernel_fpu_begin); diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c index ca4c4ca2f6af73c1fddcec2b4055ca76f34c8b4d..5cb801acc2e5ffb09664540b6026341c0c801c75 100644 --- a/arch/x86/kernel/smpboot.c +++ b/arch/x86/kernel/smpboot.c @@ -1111,7 +1111,7 @@ int native_cpu_up(unsigned int cpu, struct task_struct *tidle) return err; /* the FPU context is blank, nobody can own it */ - __cpu_invalidate_fpregs_state(cpu); + per_cpu(fpu_fpregs_owner_ctx, cpu) = NULL; common_cpu_up(cpu, tidle);