In a config file from "kernel test robot <lkp@intel.com>" 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@infradead.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: linux-ia64@vger.kernel.org
Cc: Tony Luck <tony.luck@intel.com>
Cc: kernel test robot <lkp@intel.com>
---
 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);
 
 SYSCALL_DEFINE1(exit, int, error_code)
 {

On Sat, Jan 22, 2022 at 09:48:34AM -0800, Randy Dunlap wrote:
> In a config file from "kernel test robot <lkp@intel.com>" 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@infradead.org>
> Cc: "Eric W. Biederman" <ebiederm@xmission.com>
> Cc: linux-ia64@vger.kernel.org
> Cc: Tony Luck <tony.luck@intel.com>
> Cc: kernel test robot <lkp@intel.com>
> ---
>  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.

On 1/24/22 01:20, Christoph Hellwig wrote:
> On Sat, Jan 22, 2022 at 09:48:34AM -0800, Randy Dunlap wrote:
>> In a config file from "kernel test robot <lkp@intel.com>" 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

OK, I'll send a patch to do ^^^that^^^ instead.

>> 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@infradead.org>
>> Cc: "Eric W. Biederman" <ebiederm@xmission.com>
>> Cc: linux-ia64@vger.kernel.org
>> Cc: Tony Luck <tony.luck@intel.com>
>> Cc: kernel test robot <lkp@intel.com>
>> ---
>>  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.

thanks.
-- 
~Randy