Few lines below we do drop_fpu() which is more safer. Remove the
unnecessary user_fpu_end() in save_xstate_sig(), which allows
the drop_fpu() to ignore any pending exceptions from the user-space
and drop the current fpu.
Signed-off-by: Suresh Siddha <suresh.b.sid...@intel.com>
---
arch/x86/include/asm/fpu-internal.h | 17 +++--------------
arch/x86/kernel/xsave.c | 1 -
2 files changed, 3 insertions(+), 15 deletions(-)
diff --git a/arch/x86/include/asm/fpu-internal.h
b/arch/x86/include/asm/fpu-internal.h
index fe95ad0..fac39e9 100644
--- a/arch/x86/include/asm/fpu-internal.h
+++ b/arch/x86/include/asm/fpu-internal.h
@@ -412,22 +412,11 @@ static inline void __drop_fpu(struct task_struct *tsk)
}
/*
- * The actual user_fpu_begin/end() functions
- * need to be preemption-safe.
+ * Need to be preemption-safe.
*
- * NOTE! user_fpu_end() must be used only after you
- * have saved the FP state, and user_fpu_begin() must
- * be used only immediately before restoring it.
- * These functions do not do any save/restore on
- * their own.
+ * NOTE! user_fpu_begin() must be used only immediately before restoring
+ * it. This function does not do any save/restore on their own.
*/
-static inline void user_fpu_end(void)
-{
- preempt_disable();
- __thread_fpu_end(current);
- preempt_enable();
-}
-
static inline void user_fpu_begin(void)
{
preempt_disable();
diff --git a/arch/x86/kernel/xsave.c b/arch/x86/kernel/xsave.c
index 6cfc7d9..f0bb844 100644
--- a/arch/x86/kernel/xsave.c
+++ b/arch/x86/kernel/xsave.c
@@ -254,7 +254,6 @@ int save_xstate_sig(void __user *buf, void __user *buf_fx,
int size)
/* Update the thread's fxstate to save the fsave header. */
if (ia32_fxstate)
fpu_fxsave(&tsk->thread.fpu);
- user_fpu_end();
} else {
sanitize_i387_state(tsk);
if (__copy_to_user(buf_fx, xsave, xstate_size))
--
1.7.6.5
--
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