[PATCH v2 5/7] x86/callthunk: No callthunk for restore_processor_state()

Peter Zijlstra
2023-01-16T14:53:01Z

From: Joan Bruguera <joanbrugueram@gmail.com>

When resuming from suspend we don't have coherent CPU state, trying to
do callthunks here isn't going to work. Specifically GS isn't set yet.

Fixes: e81dc127ef69 ("x86/callthunks: Add call patching for call depth tracking")
Signed-off-by: Joan Bruguera <joanbrugueram@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20230109040531.7888-1-joanbrugueram@gmail.com
---
arch/x86/kernel/callthunks.c | 5 +++++
arch/x86/power/cpu.c | 3 +++
2 files changed, 8 insertions(+)

--- a/arch/x86/kernel/callthunks.c
+++ b/arch/x86/kernel/callthunks.c
@@ -7,6 +7,7 @@
#include <linux/memory.h>
#include <linux/moduleloader.h>
#include <linux/static_call.h>
+#include <linux/suspend.h>

#include <asm/alternative.h>
#include <asm/asm-offsets.h>
@@ -151,6 +152,10 @@ static bool skip_addr(void *dest)
dest < (void*)hypercall_page + PAGE_SIZE)
return true;
#endif
+#ifdef CONFIG_PM_SLEEP
+ if (dest == restore_processor_state)
+ return true;
+#endif
return false;
}