Re: KVM induced panic on 2.6.38[2367] & 2.6.39

Avi Kivity
2011-06-01T06:56:30Z

On 06/01/2011 09:31 AM, Brad Campbell wrote:
> On 01/06/11 12:52, Hugh Dickins wrote:
>
>>
>> I guess Brad could try SLUB debugging, boot with slub_debug=P
>> for poisoning perhaps; though it might upset alignments and
>> drive the problem underground. Or see if the same happens
>> with SLAB instead of SLUB.
>
> Not much use I'm afraid.
> This is all I get in the log
>
> [ 3161.300073]
> =============================================================================
> [ 3161.300147] BUG kmalloc-512: Freechain corrupt
>
> The qemu process is then frozen, unkillable but reported in state "R"
>
> 13881 ? R 3:27 /usr/bin/qemu -S -M pc-0.13 -enable-kvm -m
> 1024 -smp 2,sockets=2,cores=1,threads=1 -nam
>
> The machine then progressively dies until it's frozen solid with no
> further error messages.
>
> I stupidly forgot to do an alt-sysrq-t prior to doing an alt-sysrq-b,
> but at least it responded to that.
>
> On the bright side I can reproduce it at will.

Please try slub_debug=FZPU; that should point the finger (hopefully at
somebody else).

--
I have a truly marvellous patch that fixes the bug which this
signature is too narrow to contain.