From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Jan Beulich" <jbeulich@novell.com>
Subject: [PATCH] small adjustment to asm constraints for c/s
	19400
Date: Fri, 27 Mar 2009 16:35:50 +0000
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Properly indicate the variable that the asm writes to, and allow
compiler more freedom in selecting a suitable input operand for the ltr
instruction.

Signed-off-by: Jan Beulich <jbeulich@novell.com>

--- 2009-03-27.orig/xen/arch/x86/traps.c	2009-03-24 09:04:02.0000000=
00 +0100
+++ 2009-03-27/xen/arch/x86/traps.c	2009-03-27 10:10:57.000000000 =
+0100
@@ -3048,8 +3048,8 @@ void load_TR(void)
=20
     /* Switch to non-compat GDT (which has B bit clear) to execute LTR. =
*/
     asm volatile (
-        "sgdt %1; lgdt %2; ltr %%ax; lgdt %1"
-        : : "a" (TSS_ENTRY << 3), "m" (old_gdt), "m" (tss_gdt) : "memory" =
);
+        "sgdt %0; lgdt %2; ltr %w1; lgdt %0"
+        : "=3Dm" (old_gdt) : "rm" (TSS_ENTRY << 3), "m" (tss_gdt) : =
"memory" );
 }
=20
 void __devinit percpu_traps_init(void)