[tip:x86/urgent] x86-64: Fix unwind annotations in recent NMI changes

From: tip-bot for Jan Beulich
Date: Thu Jan 24 2013 - 07:27:18 EST


Commit-ID: 444723dccc3c855fe88ea138cdec46f30e707b74
Gitweb: http://git.kernel.org/tip/444723dccc3c855fe88ea138cdec46f30e707b74
Author: Jan Beulich <JBeulich@xxxxxxxx>
AuthorDate: Thu, 24 Jan 2013 09:27:31 +0000
Committer: Ingo Molnar <mingo@xxxxxxxxxx>
CommitDate: Thu, 24 Jan 2013 10:56:32 +0100

x86-64: Fix unwind annotations in recent NMI changes

While in one case a plain annotation is necessary, in the other
case the stack adjustment can simply be folded into the
immediately preceding RESTORE_ALL, thus getting the correct
annotation for free.

Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>
Cc: Steven Rostedt <rostedt@xxxxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Alexander van Heukelum <heukelum@xxxxxxxxxxxxx>
Link: http://lkml.kernel.org/r/51010C9302000078000B9045@xxxxxxxxxxxxxxxxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
arch/x86/kernel/entry_64.S | 7 +++----
1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S
index 07a7a04..cb3c591 100644
--- a/arch/x86/kernel/entry_64.S
+++ b/arch/x86/kernel/entry_64.S
@@ -1781,6 +1781,7 @@ first_nmi:
* Leave room for the "copied" frame
*/
subq $(5*8), %rsp
+ CFI_ADJUST_CFA_OFFSET 5*8

/* Copy the stack frame to the Saved frame */
.rept 5
@@ -1863,10 +1864,8 @@ end_repeat_nmi:
nmi_swapgs:
SWAPGS_UNSAFE_STACK
nmi_restore:
- RESTORE_ALL 8
-
- /* Pop the extra iret frame */
- addq $(5*8), %rsp
+ /* Pop the extra iret frame at once */
+ RESTORE_ALL 6*8

/* Clear the NMI executing stack variable */
movq $0, 5*8(%rsp)
--
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