Re: [bug, netconsole, SLUB] BUG skbuff_head_cache: Poison overwritten

Christoph Lameter
2008-07-18T13:56:39Z

Pekka Enberg wrote:
> On Fri, Jul 18, 2008 at 12:11 PM, Ingo Molnar <mingo@elte.hu> wrote:
>> * Pekka J Enberg <penberg@cs.helsinki.fi> wrote:
>>
>>>> Object 0xf658ae70: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk
>>> It's bit unfortunate that we don't see full dump of the corruption
>>> here because SLUB limits the output to 128 bytes. Ingo, you might want
>>> to try this patch so that we can see all of it:
>> ok, applied this as a debug special to tip/out-of-tree - future
>> incidents should have the full object dump.
>>
>> would makes sense for upstream too i think, or increase the limit to 4K
>> or so. (which is still fair to be dumped into a syslog)
>
> SLUB already limits object sizes to less than PAGE_SIZE so the patch
> should be fine. Christoph, are you okay with this going upstream?

I am fine with the patch. Just be aware that we are going to be shoveling a lot of stuff into the log. The object size can be greater than 4k for non kmalloc slab caches. True in general object sizes are <4k.