x86/nmi/64: Minor asm simplification
Replace LEA; MOV with an equivalent SUB. This saves one
instruction.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Reviewed-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S
index d8ab2b2..0fb5252 100644
--- a/arch/x86/entry/entry_64.S
+++ b/arch/x86/entry/entry_64.S
@@ -1420,8 +1420,7 @@
* Modify the "iret" frame to point to repeat_nmi, forcing another
* iteration of NMI handling.
*/
- leaq -1*8(%rsp), %rdx
- movq %rdx, %rsp
+ subq $8, %rsp
leaq -10*8(%rsp), %rdx
pushq $__KERNEL_DS
pushq %rdx
