Re: [PATCH -next] exit: export make_task_dead()

[Christoph Hellwig]

On Sat, Jan 22, 2022 at 09:48:34AM -0800, Randy Dunlap wrote:
> In a config file from "kernel test robot <lkp@xxxxxxxxx>" for a
> different problem, this linker error was exposed when
> CONFIG_IA64_MCA_RECOVERY=m.
> 
> We could either export make_task_dead() or restrict IA64_MCA_RECOVERY
> to a bool Kconfig symbol instead of a tristate symbol, so go with the
> EXPORT_SYMBOL() path.
> 
> Fixes this build error:
> 
> ERROR: modpost: "make_task_dead" [arch/ia64/kernel/mca_recovery.ko] undefined!
> 
> Fixes: 0e25498f8cd4 ("exit: Add and use make_task_dead.")
> Signed-off-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
> Cc: "Eric W. Biederman" <ebiederm@xxxxxxxxxxxx>
> Cc: linux-ia64@xxxxxxxxxxxxxxx
> Cc: Tony Luck <tony.luck@xxxxxxxxx>
> Cc: kernel test robot <lkp@xxxxxxxxx>
> ---
>  kernel/exit.c |    1 +
>  1 file changed, 1 insertion(+)
> 
> --- linux-next-20220121.orig/kernel/exit.c
> +++ linux-next-20220121/kernel/exit.c
> @@ -896,6 +896,7 @@ void __noreturn make_task_dead(int signr
>  
>  	do_exit(signr);
>  }
> +EXPORT_SYMBOL(make_task_dead);

EXPORT_SYMBOL_GPL and restricted, please.

Or even better: force the mca recovery code to be built in.