| Message ID | 20181107194858.9380-6-bigeasy@linutronix.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [01/23] x86/fpu: Use ULL for shift in xfeature_uncompacted_offset() | expand |
diff --git a/arch/x86/kernel/fpu/core.c b/arch/x86/kernel/fpu/core.c index 9387e0fec7d17..b7d9b19ab8116 100644 --- a/arch/x86/kernel/fpu/core.c +++ b/arch/x86/kernel/fpu/core.c @@ -368,11 +368,9 @@ void fpu__clear(struct fpu *fpu) * Make sure fpstate is cleared and initialized. */ if (static_cpu_has(X86_FEATURE_FPU)) { - preempt_disable(); fpu__initialize(fpu); user_fpu_begin(); copy_init_fpstate_to_fpregs(); - preempt_enable(); } }
The preempt_disable() section was introduced in commit a10b6a16cdad8 ("x86/fpu: Make the fpu state change in fpu__clear() scheduler-atomic") and it was said to be temporary. fpu__initialize() initializes the FPU struct to its "init" value and then sets ->initialized to 1. The last part is the important one. The content of the `state' does not matter because it gets set via copy_init_fpstate_to_fpregs(). A preemption here has little meaning because the register will always be set to the same content after copy_init_fpstate_to_fpregs(). A softirq with a kernel_fpu_begin() could also force to save FPU's register after fpu__initialize() without changing the outcome here. Remove the preempt_disable() section in fpu__clear(), preemption here does not hurt. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> --- arch/x86/kernel/fpu/core.c | 2 -- 1 file changed, 2 deletions(-)