Merge branch 'x86/mpx' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 cpufeature and mpx updates from Peter Anvin:
 "This includes the basic infrastructure for MPX (Memory Protection
  Extensions) support, but does not include MPX support itself.  It is,
  however, a prerequisite for KVM support for MPX, which I believe will
  be pushed later this merge window by the KVM team.

  This includes moving the functionality in
  futex_atomic_cmpxchg_inatomic() into a new function in uaccess.h so it
  can be reused - this will be used by the final MPX patches.

  The actual MPX functionality (map management and so on) will be pushed
  in a future merge window, when ready"

* 'x86/mpx' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/intel/mpx: Remove unused LWP structure
  x86, mpx: Add MPX related opcodes to the x86 opcode map
  x86: replace futex_atomic_cmpxchg_inatomic() with user_atomic_cmpxchg_inatomic
  x86: add user_atomic_cmpxchg_inatomic at uaccess.h
  x86, xsave: Support eager-only xsave features, add MPX support
  x86, cpufeature: Define the Intel MPX feature flag

1 files changed, 1 insertions, 20 deletions

diff --git a/arch/x86/include/asm/futex.h b/arch/x86/include/asm/futex.h
index be27ba1e947a..b4c1f5453436 100644
--- a/arch/x86/include/asm/futex.h
+++ b/arch/x86/include/asm/futex.h
@@ -110,26 +110,7 @@ static inline int futex_atomic_op_inuser(int encoded_op, u32 __user *uaddr)
 static inline int futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
 						u32 oldval, u32 newval)
 {
-	int ret = 0;
-
-	if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32)))
-		return -EFAULT;
-
-	asm volatile("\t" ASM_STAC "\n"
-		     "1:\t" LOCK_PREFIX "cmpxchgl %4, %2\n"
-		     "2:\t" ASM_CLAC "\n"
-		     "\t.section .fixup, \"ax\"\n"
-		     "3:\tmov     %3, %0\n"
-		     "\tjmp     2b\n"
-		     "\t.previous\n"
-		     _ASM_EXTABLE(1b, 3b)
-		     : "+r" (ret), "=a" (oldval), "+m" (*uaddr)
-		     : "i" (-EFAULT), "r" (newval), "1" (oldval)
-		     : "memory"
-	);
-
-	*uval = oldval;
-	return ret;
+	return user_atomic_cmpxchg_inatomic(uval, uaddr, oldval, newval);
 }
 
 #endif