Re: [Qemu-devel] Qemu-KVM 0.12.3 and Multipath -> Assertion

[André Weidemann]

Hi Kevin,
On 04.05.2010 14:20, Kevin Wolf wrote:

> Am 04.05.2010 13:38, schrieb Peter Lieven:
> > hi kevin,
> >
> > i set a breakpint at bmdma_active_if. the first 2 breaks encountered
> > when the last path in the multipath
> > failed, but the assertion was not true.
> > when i kicked one path back in the breakpoint was reached again, this
> > time leading to an assert.
> > the stacktrace is from the point shortly before.
> >
> > hope this helps.
>
> Hm, looks like there's something wrong with cancelling requests -
> bdrv_aio_cancel might decide that it completes a request (and
> consequently calls the callback for it) whereas the IDE emulation
> decides that it's done with the request before calling bdrv_aio_cancel.
>
> I haven't looked in much detail what this could break, but does
> something like this help?

Your attached patch fixes the problem I had as well. I ran 3 consecutive 
tests tonight, which all finished without crashing the VM.
I reported my "assertion failed" error on March 14th while doing disk 
perfomance tests using iozone in an Ubuntu 9.10 VM with qemu-kvm 0.12.3.

Thank you very much.
 André