Re: NULL pointer in kmem_cache_alloc with 2.6.25-rc1

From: Zhang, Yanmin
Date: Tue Feb 19 2008 - 02:07:35 EST


On Fri, 2008-02-15 at 08:42 -0800, Christoph Lameter wrote:
> On Fri, 15 Feb 2008, Zhang, Yanmin wrote:
>
> > On my 16-core tigerton, kernel panic when I ran hackbench process testing. See
> > below log.
> >
>
> > Kernel panic at line 1637 in file mm/slub.c because object=c->freelist=NULL.
>
> Hmmmm. freelist should never be NULL. Could you rerun the test and boot with
> slub_debug to make sure that there is no memory corruption?
1) Without slub_debug option, sometime I could trigger it, sometimes not.
2) With slub_debug option, or just enable debug for slab skbuff_fclone_cache
and skbuff_head_cache, I couldn't trigger it.

I will do more testing and investigation, as the bug also exists in 2.6.25-rc2.

-yanmin


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/