Re: [Qemu-devel] dataplane: latest rc with selected patches hangs very often

[Paolo Bonzini]

Il 11/07/2014 21:18, Andrey Korolyov ha scritto:
> On Fri, Jul 11, 2014 at 11:01 PM, Andrey Korolyov <address@hidden> wrote:
> > Hello,
> >
> > is it worthy to re-test dp until next tag point? I am checking aio
> > with -rc1 and following picked commits (sorry for patchwork
> > references):
> >
> > stefanha:
> > 368191 New          [v3,1/4] virtio-blk: avoid dataplane
> > VirtIOBlockReq early free
> > 368787 New          [v3,2/4] dataplane: do not free VirtQueueElement
> > in vring_push()
> > 368360 New          [v3,3/4] virtio-blk: avoid g_slice_new0() for
> > VirtIOBlockReq and VirtQueueElement
> > 368863 New          [v3,4/4] virtio-blk: embed VirtQueueElement in
> > VirtIOBlockReq
> >
> > pbonzini:
> > 367551 New          [1/4] block: prefer aio_poll to qemu_aio_wait
> > 367553 New          [2/4] block: drop aio functions that operate on
> > the main AioContext
> > 367552 New          [3/4] test-aio: fix GSource-based timer test
> > 367554 New          [4/4] AioContext: speed up aio_notify
> >
> > Emulator itself stop responding in approximately ninety percent of
> > cases, e.g. it does not react to anything except SIGKILL. Windows VM
> > is able to read some bits before lockup happens because it draws an
> > initial logo.

Please try this patch:

http://article.gmane.org/gmane.comp.emulators.qemu/285674/raw

Paolo

> > hangs on vl.c:
> > (gdb) list
> > 2890        g_free(dummy);
> > 2891        if (err) {
> > 2892            qerror_report_err(err);
> > 2893            return -1;
> > 2894        }
> > 2895        return 0;
> > 2896    }
> > 2897
> > 2898    int main(int argc, char **argv, char **envp)
> > 2899    {
> > (gdb) next
> > Single stepping until exit from function __lll_lock_wait,
> > which has no line number information.
> >
> > cmdline follows:
> > if=none,id=drive-virtio-disk0,format=raw,cache=writeback,aio=native
> > ... -object iothread,id=blk0 -set device.virtio-disk0.config-wce=off
> > -set device.virtio-disk0.scsi=off -set
> > device.virtio-disk0.iothread=blk0
>
> Forgot to attach backtrace, though the issue and bt itself can be
> easily reproduced.