Re: [PATCH] x86/fpu: drop_fpu() should not assume that tsk == current

Rik van Riel
2015-03-09T17:36:34Z

On 03/09/2015 01:10 PM, Oleg Nesterov wrote:
> drop_fpu() does clear_used_math() and usually this is correct because
> tsk == current. However switch_fpu_finish()->restore_fpu_checking() is
> called before it updates the "current_task" variable. If it fails, we
> will wrongly clear the PF_USED_MATH flag of the previous task.

Ouch. Good catch.

> Signed-off-by: Oleg Nesterov <oleg@redhat.com>
> Cc: <stable@vger.kernel.org>

Reviewed-by: Rik van Riel <riel@redhat.com>