Re: [Qemu-devel] [Bug 1013241] Re: qemu-system-ppc64 hanging occasionally in disk writes

[Benjamin Herrenschmidt]

On Tue, 2012-06-19 at 10:16 +0000, Richard W.M. Jones wrote:
> I switched to using virtio-scsi (instead of virtio-blk).  This appears to 
> have solved
> this problem, although it brings another problem.  I also tried vscsi, which 
> fixes
> both problems.
> 
> Therefore I will (not definitively) claim that the problem lies somewhere in 
> virtio-blk,
> but a workaround seems to be available.

What was the virtio-scsi problem ? (Other than SLOF doesn't know about
it yet :-) I haven't audited/tested it so it might have endian issues...

I have reproduced a similar hang with vscsi in full emulation, I haven't
observed your problem with virtio-blk, I plan to spend more time doing
some torture testing & debugging this week see if I can find out what's
going on.

BTW. What was your guest kernel version ?

Cheers,
Ben.