[PATCH 3/4] x86,objtool: Mark cpu_startup_entry() __noreturn

From: Peter Zijlstra
Date: Fri Apr 08 2022 - 05:48:06 EST


GCC-8 isn't clever enough to figure out that cpu_start_entry() is a
noreturn while objtool is. This results in code after the call in
start_secondary(). Give GCC a hand so that they all agree on things.

vmlinux.o: warning: objtool: start_secondary()+0x10e: unreachable

Reported-by: Rick Edgecombe <rick.p.edgecombe@xxxxxxxxx>
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
---
include/linux/cpu.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/include/linux/cpu.h
+++ b/include/linux/cpu.h
@@ -167,7 +167,7 @@ static inline int suspend_disable_second
static inline void suspend_enable_secondary_cpus(void) { }
#endif /* !CONFIG_PM_SLEEP_SMP */

-void cpu_startup_entry(enum cpuhp_state state);
+void __noreturn cpu_startup_entry(enum cpuhp_state state);

void cpu_idle_poll_ctrl(bool enable);