Re: [PATCH v2 1/3] panic: Introduce arch_do_panic

Mete Durlu <[email protected]> Tue, 28 Jul 2026 12:13:33 +0200
Newsgroups org.kernel.vger.sparclinux,org.kernel.vger.linux-kernel,org.kernel.vger.linux-s390
Message-ID <[email protected]>
On 27/07/2026 14:59, Bradley Morgan wrote:
> Hi Mete,

Hi Bradley,

>> +#ifndef arch_do_panic
>> +#define arch_do_panic arch_do_panic
>> +static inline void arch_do_panic(void) {}
>> +#endif
> 
> this is fragile. the arch override only kicks in if whatever header
> defines the macro happens to be in panic.c's include chain. if it ever
> falls out, the empty stub wins silently, the arch version still
> compiles as a global nobody calls, and the hook is just dead. no build
> break, no warning, nothing.
> 
> use a weak function instead.

While I acknowledge the benefits you just listed, I got the
notion that maintainers don't prefer __weak implementations
and instead opt for arch specific override via ifndef guards.
Therefore I wanted to start with this approach.

However I am willing to switch if the maintainers would favor
that approach.
> 
> one more thing on the call site: arch code now runs (and prints, on
> sparc) after the "end Kernel panic" marker, which until now was the
> last line anyone would ever see. tools grep for that as a terminal
> marker. probably fine, but say so in the changelog instead of leaving
> it implicit.

Right, I'll mention that. And by changelog I take it that you mean
the commit message, right?

> s/already has/already have/ in the changelog while your at it.

Thanks, I'll fix the typo in the next version.