lkml.org 
[lkml]   [2022]   [Apr]   [11]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
SubjectRe: [PATCH 3/4] x86,objtool: Mark cpu_startup_entry() __noreturn
On Fri, Apr 08, 2022 at 11:45:55AM +0200, Peter Zijlstra wrote:
> 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@intel.com>
> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
> ---
> 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);

I just ran into this:

init/main.o: warning: objtool: rest_init() falls through to next function kernel_init()

so we need this as well:

diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index 565fec451d69..fab2235599a0 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -184,6 +184,7 @@ static bool __dead_end_function(struct objtool_file *file, struct symbol *func,
"do_group_exit",
"stop_this_cpu",
"__invalid_creds",
+ "cpu_startup_entry",
};

if (!func)
\
 
 \ /
  Last update: 2022-04-11 22:33    [W:0.081 / U:0.848 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site