Re: [PATCH] lib/bug: make panic_on_warn available for all architectures

[Heiko Carstens]

On Tue, Jan 26, 2016 at 03:14:08PM -0800, Andrew Morton wrote:
> On Fri, 22 Jan 2016 14:12:16 +0100 Heiko Carstens <heiko.carstens@xxxxxxxxxx> wrote:
> 
> > Christian Borntraeger reported that panic_on_warn doesn't have any
> > effect on s390.
> > 
> > The panic_on_warn feature was introduced with 9e3961a09798 ("kernel:
> > add panic_on_warn"). However it did care only for the case when
> > WANT_WARN_ON_SLOWPATH is defined. This is turn is only the case for
> > architectures which do not have an own __WARN_TAINT defined.
> > 
> > Other architectures which do have __WARN_TAINT defined call
> > report_bug() for warnings within lib/bug.c which does not call panic()
> > in case panic_on_warn is set.
> > 
> > Let's simply enable the panic_on_warn feature by adding the same code
> > like it was added to warn_slowpath_common() in panic.c.
> > 
> > This enables panic_on_warn also for arm64, parisc, powerpc, s390 and
> > sh.
> > 
> 
> It's a bit sad to do this in two places.  You couldn't find a suitable
> place which is effective for all architectures?

Yes, I know, it's lame. But looking at lib/bug.c:report_bug() and
kernel/panic.c:warn_slowpath_common() it looks like these functions have a
lot in common but differ in detail. It seems hard to combine them without
introducing an ifdef hell.