Subject: Re: [PATCH] slub: fix kernel BUG at mm/slub.c:1950!

From: Pekka Enberg <[email-masked]>
Date: Mon, 13 Jun 2011 21:34:08 +0300

On Mon, 2011-06-13 at 12:59 -0500, Christoph Lameter wrote:
> On Sun, 12 Jun 2011, Hugh Dickins wrote:
> 
> > 3.0-rc won't boot with SLUB on my PowerPC G5: kernel BUG at mm/slub.c:1950!
> > Bisected to 1759415e630e "slub: Remove CONFIG_CMPXCHG_LOCAL ifdeffery".
> >
> > After giving myself a medal for finding the BUG on line 1950 of mm/slub.c
> > (it's actually the
> > 	VM_BUG_ON((unsigned long)(&pcp1) % (2 * sizeof(pcp1)));
> > on line 268 of the morass that is include/linux/percpu.h)
> > I tried the following alignment patch and found it to work.
> 
> Hmmm.. The allocpercpu in alloc_kmem_cache_cpus should take care of the
> alignment. Uhh.. I see that a patch that removes the #ifdef CMPXCHG_LOCAL
> was not applied? Pekka?

This patch?

http://git.kernel.org/?p=linux/kernel/git/penberg/slab-2.6.git;a=commitdiff;h=d4d84fef6d0366b585b7de13527a0faeca84d9ce

It's queued and will be sent to Linus soon.

			Pekka