diff options
| author | Oleg Nesterov <oleg@redhat.com> | 2014-09-02 19:57:17 +0200 |
|---|---|---|
| committer | Jiri Slaby <jslaby@suse.cz> | 2014-11-13 19:02:12 +0100 |
| commit | 03f43efc6a00eb29015222f8e9caeafdd9986a63 (patch) | |
| tree | dcf13d620b4d3244a61f74d12ba14f1bb7a5d0fb /arch | |
| parent | 19ad5dfd81d7bebf89a9a5c49ab0bc2bc6187ae7 (diff) | |
x86, fpu: __restore_xstate_sig()->math_state_restore() needs preempt_disable()
commit df24fb859a4e200d9324e2974229fbb7adf00aef upstream.
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
Reviewed-by: Suresh Siddha <sbsiddha@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Diffstat (limited to 'arch')
| -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 422fd8223470..7305625c2767 100644 --- a/arch/x86/kernel/xsave.c +++ b/arch/x86/kernel/xsave.c @@ -399,8 +399,11 @@ 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 { |