Re: [PATCH 1/5] s390/ipl: Mark store_status as __noreturn

From: Thorsten Blum
Date: Tue Nov 11 2025 - 02:11:21 EST


On 10. Nov 2025, at 16:06, Heiko Carstens wrote:
> On Mon, Nov 10, 2025 at 02:27:51PM +0100, Thorsten Blum wrote:
>> store_status() performs a tail call (BR_EX) to the function passed as
>> the first parameter and does not return. Annotate the declaration with
>> the __noreturn attribute to improve compiler optimizations.
>>
>> Signed-off-by: Thorsten Blum <thorsten.blum@xxxxxxxxx>
>> ---
>> arch/s390/include/asm/ipl.h | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> This doesn't make any sense. If a function is called, which calls
> another one with a tail call, then _of course_ it looks to the caller
> like the function returned.

Hm, I must have misunderstood this comment from
arch/s390/kernel/machine_kexec.c:

/*
* ...
* The call to store_status() will not return.
*/
store_status(__do_machine_kdump, image);