Re: [PATCH 3/3] x86, fpu: kill save_init_fpu(), change math_error() to use unlazy_fpu()

From: Rik van Riel
Date: Thu Jan 29 2015 - 16:54:55 EST


On 01/29/2015 04:08 PM, Oleg Nesterov wrote:
> math_error() calls save_init_fpu() after conditional_sti(), this means
> that the caller can be preempted. If !use_eager_fpu() we can hit the
> WARN_ON_ONCE(!__thread_has_fpu(tsk)) and/or save the wrong FPU state.
>
> Change math_error() to use unlazy_fpu() and kill save_init_fpu().
>
> Signed-off-by: Oleg Nesterov <oleg@xxxxxxxxxx>

Reviewed-by: Rik van Riel <riel@xxxxxxxxxx>

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