1 files changed, 18 insertions, 15 deletions

diff --git a/arch/x86/include/asm/xsave.h b/arch/x86/include/asm/xsave.h
index 8b75824e41dd..0d1523146545 100644
--- a/arch/x86/include/asm/xsave.h
+++ b/arch/x86/include/asm/xsave.h
@@ -145,6 +145,16 @@ static inline int fpu_xrstor_checking(struct xsave_struct *fx)
         return xrstor_state(fx, -1);
 }
 
+/*
+ * Save xstate to user space xsave area.
+ *
+ * We don't use modified optimization because xrstor/xrstors might track
+ * a different application.
+ *
+ * We don't use compacted format xsave area for
+ * backward compatibility for old applications which don't understand
+ * compacted format of xsave area.
+ */
 static inline int xsave_user(struct xsave_struct __user *buf)
 {
         int err;
@@ -158,35 +168,28 @@ static inline int xsave_user(struct xsave_struct __user *buf)
                 return -EFAULT;
 
         __asm__ __volatile__(ASM_STAC "\n"
-                             "1: .byte " REX_PREFIX "0x0f,0xae,0x27\n"
+                             "1:"XSAVE"\n"
                              "2: " ASM_CLAC "\n"
-                             ".section .fixup,\"ax\"\n"
-                             "3:  movl $-1,%[err]\n"
-                             "    jmp  2b\n"
-                             ".previous\n"
-                             _ASM_EXTABLE(1b,3b)
-                             : [err] "=r" (err)
+                             xstate_fault
                              : "D" (buf), "a" (-1), "d" (-1), "0" (0)
                              : "memory");
         return err;
 }
 
+/*
+ * Restore xstate from user space xsave area.
+ */
 static inline int xrestore_user(struct xsave_struct __user *buf, u64 mask)
 {
-        int err;
+        int err = 0;
         struct xsave_struct *xstate = ((__force struct xsave_struct *)buf);
         u32 lmask = mask;
         u32 hmask = mask >> 32;
 
         __asm__ __volatile__(ASM_STAC "\n"
-                             "1: .byte " REX_PREFIX "0x0f,0xae,0x2f\n"
+                             "1:"XRSTOR"\n"
                              "2: " ASM_CLAC "\n"
-                             ".section .fixup,\"ax\"\n"
-                             "3:  movl $-1,%[err]\n"
-                             "    jmp  2b\n"
-                             ".previous\n"
-                             _ASM_EXTABLE(1b,3b)
-                             : [err] "=r" (err)
+                             xstate_fault
                              : "D" (xstate), "a" (lmask), "d" (hmask), "0" (0)
                              : "memory");       /* memory required? */
         return err;