Re: [Qemu-devel] [PATCH 0/4] Tweaks around virtio-blk start/stop

[tu bo]

On 03/16/2016 09:38 PM, Christian Borntraeger wrote:
> On 03/16/2016 01:55 PM, Paolo Bonzini wrote:
> > On 16/03/2016 12:24, Christian Borntraeger wrote:
> > > On 03/16/2016 12:09 PM, Paolo Bonzini wrote:
> > > > On 16/03/2016 11:49, Christian Borntraeger wrote:
> > > > > #3  0x00000000800b713e in virtio_blk_data_plane_start (s=0xba232d80) at 
> > > > > /home/cborntra/REPOS/qemu/hw/block/dataplane/virtio-blk.c:224
> > > > > #4  0x00000000800b4ea0 in virtio_blk_handle_output (vdev=0xb9eee7e8, 
> > > > > vq=0xba305270) at /home/cborntra/REPOS/qemu/hw/block/virtio-blk.c:590
> > > > > #5  0x00000000800ef3dc in virtio_queue_notify_vq (vq=0xba305270) at 
> > > > > /home/cborntra/REPOS/qemu/hw/virtio/virtio.c:1095
> > > > > #6  0x00000000800f1c9c in virtio_queue_host_notifier_read (n=0xba3052c8) at 
> > > > > /home/cborntra/REPOS/qemu/hw/virtio/virtio.c:1785
> >
> > If you just remove the calls to virtio_queue_host_notifier_read, here
> > and in virtio_queue_aio_set_host_notifier_fd_handler, does it work
> > (keeping patches 2-4 in)?
>
> With these changes and patch 2-4 it does no longer locks up.
> I keep it running some hour to check if a crash happens.
>
> Tu Bo, your setup is currently better suited for reproducing. Can you also 
> check?

remove the calls to virtio_queue_host_notifier_read, and keeping patches 
2-4 in,

I got same crash as before,
(gdb) bt
#0  bdrv_co_do_rw (opaque=0x0) at block/io.c:2172
#1  0x000002aa0c65d786 in coroutine_trampoline (i0=<optimized out>, 
i1=-2013204784) at util/coroutine-ucontext.c:79
#2  0x000003ff99ad150a in __makecontext_ret () from /lib64/libc.so.6


> > Paolo
> >
> > > > > #7  0x00000000800f1e14 in virtio_queue_set_host_notifier_fd_handler 
> > > > > (vq=0xba305270, assign=false, set_handler=false) at 
> > > > > /home/cborntra/REPOS/qemu/hw/virtio/virtio.c:1817
> > > > > #8  0x0000000080109c50 in virtio_ccw_set_guest2host_notifier (dev=0xb9eed6a0, 
> > > > > n=0, assign=false, set_handler=false) at 
> > > > > /home/cborntra/REPOS/qemu/hw/s390x/virtio-ccw.c:97
> > > > > #9  0x0000000080109ef2 in virtio_ccw_stop_ioeventfd (dev=0xb9eed6a0) at 
> > > > > /home/cborntra/REPOS/qemu/hw/s390x/virtio-ccw.c:154