[PATCH] i386: NMI pointer comparison fix

Instruction pointer comparisons for the NMI on debug stack check/fixup
were incorrect.

From: Jan Beulich <jbeulich@novell.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Zwane Mwaikambo <zwane@holomorphy.com>
Acked-by: "Seth, Rohit" <rohit.seth@intel.com>
Cc: Zachary Amsden <zach@vmware.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

arch/i386/kernel/entry.S

@@ -560,11 +560,10 @@ nmi_stack_fixup:
 nmi_debug_stack_check:
 	cmpw $__KERNEL_CS,16(%esp)
 	jne nmi_stack_correct
-	cmpl $debug - 1,(%esp)
-	jle nmi_stack_correct
+	cmpl $debug,(%esp)
+	jb nmi_stack_correct
 	cmpl $debug_esp_fix_insn,(%esp)
-	jle nmi_debug_stack_fixup
-nmi_debug_stack_fixup:
+	ja nmi_stack_correct
 	FIX_STACK(24,nmi_stack_correct, 1)
 	jmp nmi_stack_correct