The assembly PV_UNLOCK function is a callable non-leaf function which
doesn't honor CONFIG_FRAME_POINTER, which can result in bad stack
traces.
Create a stack frame when CONFIG_FRAME_POINTER is enabled.
Signed-off-by: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
Cc: Waiman Long <Waiman.Long@xxxxxxx>
---
arch/x86/include/asm/qspinlock_paravirt.h | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/arch/x86/include/asm/qspinlock_paravirt.h b/arch/x86/include/asm/qspinlock_paravirt.h
index 9f92c18..9d55f9b 100644
--- a/arch/x86/include/asm/qspinlock_paravirt.h
+++ b/arch/x86/include/asm/qspinlock_paravirt.h
@@ -36,8 +36,10 @@ PV_CALLEE_SAVE_REGS_THUNK(__pv_queued_spin_unlock_slowpath);
*/
asm (".pushsection .text;"
".globl " PV_UNLOCK ";"
+ ".type " PV_UNLOCK ", @function;"
".align 4,0x90;"
PV_UNLOCK ": "
+ FRAME_BEGIN
"push %rdx;"
"mov $0x1,%eax;"
"xor %edx,%edx;"
@@ -45,6 +47,7 @@ asm (".pushsection .text;"
"cmp $0x1,%al;"
"jne .slowpath;"
"pop %rdx;"
+ FRAME_END
"ret;"
".slowpath: "
"push %rsi;"
@@ -52,6 +55,7 @@ asm (".pushsection .text;"
"call " PV_UNLOCK_SLOWPATH ";"
"pop %rsi;"
"pop %rdx;"
+ FRAME_END
"ret;"
".size " PV_UNLOCK ", .-" PV_UNLOCK ";"
".popsection");
--
2.4.3
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