diff --git a/[refs] b/[refs]
index 1c12e7edf4b9..01fb1e0236f2 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 847815760cc0f41985b3185d780aa4369fcb475d
+refs/heads/master: ff347b221512a83e7b08356729e3e2c14346e29e
diff --git a/trunk/arch/x86_64/kernel/traps.c b/trunk/arch/x86_64/kernel/traps.c
index 64a59cb49411..77658f7f4e84 100644
--- a/trunk/arch/x86_64/kernel/traps.c
+++ b/trunk/arch/x86_64/kernel/traps.c
@@ -795,13 +795,16 @@ asmlinkage void do_coprocessor_error(struct pt_regs *regs)
 	 */
 	cwd = get_fpu_cwd(task);
 	swd = get_fpu_swd(task);
-	switch (((~cwd) & swd & 0x3f) | (swd & 0x240)) {
+	switch (swd & ~cwd & 0x3f) {
 		case 0x000:
 		default:
 			break;
 		case 0x001: /* Invalid Op */
-		case 0x041: /* Stack Fault */
-		case 0x241: /* Stack Fault | Direction */
+			/*
+			 * swd & 0x240 == 0x040: Stack Underflow
+			 * swd & 0x240 == 0x240: Stack Overflow
+			 * User must clear the SF bit (0x40) if set
+			 */
 			info.si_code = FPE_FLTINV;
 			break;
 		case 0x002: /* Denormalize */