[PATCH 13/46] x86/preempt, lto: Mark preempt_schedule_*thunk() as __visible

From: Jiri Slaby (SUSE)
Date: Mon Nov 14 2022 - 06:45:18 EST


From: Andi Kleen <andi@xxxxxxxxxxxxxx>

Symbols referenced from assembler (either directly or e.f. from
DEFINE_STATIC_KEY()) need to be global and visible in gcc LTO because
they could end up in a different object file than the assembler. This
can lead to linker errors without this patch.

So mark preempt_schedule_thunk() and preempt_schedule_notrace_thunk() as
__visible.

Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Cc: "H. Peter Anvin" <hpa@xxxxxxxxx>
Cc: x86@xxxxxxxxxx
Signed-off-by: Andi Kleen <andi@xxxxxxxxxxxxxx>
Signed-off-by: Martin Liska <mliska@xxxxxxx>
Signed-off-by: Jiri Slaby <jslaby@xxxxxxx>
---
arch/x86/include/asm/preempt.h | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/include/asm/preempt.h b/arch/x86/include/asm/preempt.h
index 5f6daea1ee24..c76ec881b23c 100644
--- a/arch/x86/include/asm/preempt.h
+++ b/arch/x86/include/asm/preempt.h
@@ -106,13 +106,13 @@ static __always_inline bool should_resched(int preempt_offset)
#ifdef CONFIG_PREEMPTION

extern asmlinkage void preempt_schedule(void);
-extern asmlinkage void preempt_schedule_thunk(void);
+extern __visible asmlinkage void preempt_schedule_thunk(void);

#define preempt_schedule_dynamic_enabled preempt_schedule_thunk
#define preempt_schedule_dynamic_disabled NULL

extern asmlinkage void preempt_schedule_notrace(void);
-extern asmlinkage void preempt_schedule_notrace_thunk(void);
+extern __visible asmlinkage void preempt_schedule_notrace_thunk(void);

#define preempt_schedule_notrace_dynamic_enabled preempt_schedule_notrace_thunk
#define preempt_schedule_notrace_dynamic_disabled NULL
--
2.38.1