[PATCH 08/46] static_call, lto: Mark static keys as __visible

Jiri Slaby (SUSE)
2022-11-14T11:44:49Z

From: Andi Kleen <andi@firstfloor.org>

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 static call functions as __visible, namely static keys here.

Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Josh Poimboeuf <jpoimboe@kernel.org>
Cc: Jason Baron <jbaron@akamai.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Martin Liska <mliska@suse.cz>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
include/linux/static_call.h | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/include/linux/static_call.h b/include/linux/static_call.h
index df53bed9d71f..e629ab0c4ca3 100644
--- a/include/linux/static_call.h
+++ b/include/linux/static_call.h
@@ -182,7 +182,7 @@ extern long __static_call_return0(void);

#define DEFINE_STATIC_CALL(name, _func) \
DECLARE_STATIC_CALL(name, _func); \
- struct static_call_key STATIC_CALL_KEY(name) = { \
+ __visible struct static_call_key STATIC_CALL_KEY(name) = { \
.func = _func, \
.type = 1, \
}; \
@@ -190,7 +190,7 @@ extern long __static_call_return0(void);

#define DEFINE_STATIC_CALL_NULL(name, _func) \
DECLARE_STATIC_CALL(name, _func); \
- struct static_call_key STATIC_CALL_KEY(name) = { \
+ __visible struct static_call_key STATIC_CALL_KEY(name) = { \
.func = NULL, \
.type = 1, \
}; \
@@ -198,7 +198,7 @@ extern long __static_call_return0(void);

#define DEFINE_STATIC_CALL_RET0(name, _func) \
DECLARE_STATIC_CALL(name, _func); \
- struct static_call_key STATIC_CALL_KEY(name) = { \
+ __visible struct static_call_key STATIC_CALL_KEY(name) = { \
.func = __static_call_return0, \
.type = 1, \
}; \
@@ -227,14 +227,14 @@ static inline int static_call_init(void) { return 0; }

#define DEFINE_STATIC_CALL(name, _func) \
DECLARE_STATIC_CALL(name, _func); \
- struct static_call_key STATIC_CALL_KEY(name) = { \
+ __visible struct static_call_key STATIC_CALL_KEY(name) = { \
.func = _func, \
}; \
ARCH_DEFINE_STATIC_CALL_TRAMP(name, _func)

#define DEFINE_STATIC_CALL_NULL(name, _func) \
DECLARE_STATIC_CALL(name, _func); \
- struct static_call_key STATIC_CALL_KEY(name) = { \
+ __visible struct static_call_key STATIC_CALL_KEY(name) = { \
.func = NULL, \
}; \
ARCH_DEFINE_STATIC_CALL_NULL_TRAMP(name)
@@ -288,7 +288,7 @@ static inline long __static_call_return0(void)

#define __DEFINE_STATIC_CALL(name, _func, _func_init) \
DECLARE_STATIC_CALL(name, _func); \
- struct static_call_key STATIC_CALL_KEY(name) = { \
+ __visible struct static_call_key STATIC_CALL_KEY(name) = { \
.func = _func_init, \
}

--
2.38.1