diff options
| author | Oleg Nesterov <oleg@redhat.com> | 2014-09-02 19:57:17 +0200 |
|---|---|---|
| committer | H. Peter Anvin <hpa@linux.intel.com> | 2014-09-02 14:51:15 -0700 |
| commit | df24fb859a4e200d9324e2974229fbb7adf00aef (patch) | |
| tree | 948fce3a30171ba27d8656f0782b9e9b9f51e864 | |
| parent | 66463db4fc5605d51c7bb81d009d5bf30a783a2c (diff) | |
| download | tip-df24fb859a4e200d9324e2974229fbb7adf00aef.tar.gz | |
x86, fpu: __restore_xstate_sig()->math_state_restore() needs preempt_disable()
Add preempt_disable() + preempt_enable() around math_state_restore() in
__restore_xstate_sig(). Otherwise __switch_to() after __thread_fpu_begin()
can overwrite fpu->state we are going to restore.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Link: http://lkml.kernel.org/r/20140902175717.GA21649@redhat.com
Cc: <stable@vger.kernel.org> # v3.7+
Reviewed-by: Suresh Siddha <sbsiddha@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
| -rw-r--r-- | arch/x86/kernel/xsave.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/arch/x86/kernel/xsave.c b/arch/x86/kernel/xsave.c index cf0b83040ec8ff..4c540c4719d80d 100644 --- a/arch/x86/kernel/xsave.c +++ b/arch/x86/kernel/xsave.c @@ -400,8 +400,11 @@ int __restore_xstate_sig(void __user *buf, void __user *buf_fx, int size) set_used_math(); } - if (use_eager_fpu()) + if (use_eager_fpu()) { + preempt_disable(); math_state_restore(); + preempt_enable(); + } return err; } else { |