[PATCH 20/33] x86/asm/power: Create stack frames in hibernate_asm_64.S

From: Josh Poimboeuf
Date: Thu Jan 21 2016 - 17:51:52 EST


swsusp_arch_suspend() and restore_registers() are callable non-leaf
functions which don't honor CONFIG_FRAME_POINTER, which can result in
bad stack traces. Also they aren't annotated as ELF callable functions
which can confuse tooling.

Create a stack frame for them when CONFIG_FRAME_POINTER is enabled and
give them proper ELF function annotations.

Signed-off-by: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
Acked-by: Pavel Machek <pavel@xxxxxx>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Reviewed-by: Borislav Petkov <bp@xxxxxxx>
---
arch/x86/power/hibernate_asm_64.S | 7 +++++++
1 file changed, 7 insertions(+)

diff --git a/arch/x86/power/hibernate_asm_64.S b/arch/x86/power/hibernate_asm_64.S
index e2386cb..4400a43 100644
--- a/arch/x86/power/hibernate_asm_64.S
+++ b/arch/x86/power/hibernate_asm_64.S
@@ -21,8 +21,10 @@
#include <asm/page_types.h>
#include <asm/asm-offsets.h>
#include <asm/processor-flags.h>
+#include <asm/frame.h>

ENTRY(swsusp_arch_suspend)
+ FRAME_BEGIN
movq $saved_context, %rax
movq %rsp, pt_regs_sp(%rax)
movq %rbp, pt_regs_bp(%rax)
@@ -50,7 +52,9 @@ ENTRY(swsusp_arch_suspend)
movq %rax, restore_cr3(%rip)

call swsusp_save
+ FRAME_END
ret
+ENDPROC(swsusp_arch_suspend)

ENTRY(restore_image)
/* switch to temporary page tables */
@@ -107,6 +111,7 @@ ENTRY(core_restore_code)
*/

ENTRY(restore_registers)
+ FRAME_BEGIN
/* go back to the original page tables */
movq %rbx, %cr3

@@ -147,4 +152,6 @@ ENTRY(restore_registers)
/* tell the hibernation core that we've just restored the memory */
movq %rax, in_suspend(%rip)

+ FRAME_END
ret
+ENDPROC(restore_registers)
--
2.4.3