Re: [Qemu-devel] make check: crash in vhost-user chardev cleanup

["Dr. David Alan Gilbert" <dgilbert@redhat.com>]

* Marc-André Lureau (marcandre.lureau@gmail.com) wrote:
> Hi
> 
> On Fri, Feb 24, 2017 at 11:54 PM Dr. David Alan Gilbert <dgilbert@redhat.com>
> wrote:
> 
> > Hi,
> >   I'm seeing a hang+crash doing a make check that
> > looks like it's coming from vhost-user's chardev cleanup,
> > so I'm suspecting your e0b283e7c.
> > The synptom is that the make check hangs in the qtest
> > part, and a dmesg shows that a qemu crashed.
> >
> 
> See that thread:
> https://lists.nongnu.org/archive/html/qemu-devel/2017-02/msg06015.html

Ah OK, as long as it's known about.  It's a reliable crash in my main build
world on my laptop.

Dave

> 
> > I got a backtrace that shows:
> >
> > (gdb) where
> > #0  0x0000560d3344f03e in qemu_chr_fe_read_all (be=be@entry=0x0,
> > buf=buf@entry=0x7ffea7a2f520 "\v", len=len@entry=12) at
> > /home/dgilbert/git/qemu/chardev/char.c:209
> > #1  0x0000560d33199d64 in vhost_user_read (msg=msg@entry=0x7ffea7a2f520,
> > dev=<optimized out>)
> >     at /home/dgilbert/git/qemu/hw/virtio/vhost-user.c:125
> > #2  0x0000560d3319a11f in vhost_user_get_vring_base (dev=0x560d35a614a0,
> > ring=0x7ffea7a2f670)
> >     at /home/dgilbert/git/qemu/hw/virtio/vhost-user.c:417
> > #3  0x0000560d33196abb in vhost_virtqueue_stop (dev=dev@entry=0x560d35a614a0,
> > vdev=vdev@entry=0x560d3729cc00, vq=0x560d35a61678, idx=1) at
> > /home/dgilbert/git/qemu/hw/virtio/vhost.c:1070
> > #4  0x0000560d33198cd4 in vhost_dev_stop (hdev=hdev@entry=0x560d35a614a0,
> > vdev=vdev@entry=0x560d3729cc00)
> >     at /home/dgilbert/git/qemu/hw/virtio/vhost.c:1533
> > #5  0x0000560d3317bfd8 in vhost_net_stop_one (net=0x560d35a614a0,
> > dev=0x560d3729cc00)
> >     at /home/dgilbert/git/qemu/hw/net/vhost_net.c:288
> > #6  0x0000560d3317c4aa in vhost_net_stop (dev=dev@entry=0x560d3729cc00,
> > ncs=<optimized out>, total_queues=total_queues@entry=1) at
> > /home/dgilbert/git/qemu/hw/net/vhost_net.c:367
> > #7  0x0000560d33179201 in virtio_net_vhost_status (status=<optimized out>,
> > n=0x560d3729cc00)
> >     at /home/dgilbert/git/qemu/hw/net/virtio-net.c:176
> > #8  0x0000560d33179201 in virtio_net_set_status (vdev=0x560d3729cc00,
> > status=7 '\a')
> >     at /home/dgilbert/git/qemu/hw/net/virtio-net.c:250
> > #9  0x0000560d3339ce99 in qemu_del_net_client (nc=0x560d35a61250) at
> > /home/dgilbert/git/qemu/net/net.c:390
> > #10 0x0000560d3339e30d in net_cleanup () at
> > /home/dgilbert/git/qemu/net/net.c:1454
> > #11 0x0000560d330ee940 in main (argc=<optimized out>, argv=<optimized
> > out>, envp=<optimized out>)
> >     at /home/dgilbert/git/qemu/vl.c:4637
> > (gdb)
> >
> > #0  qemu_chr_fe_read_all (be=be@entry=0x0, buf=buf@entry=0x7ffea7a2f520
> > "\v", len=len@entry=12)
> >     at /home/dgilbert/git/qemu/chardev/char.c:209
> > 209         Chardev *s = be->chr;
> >
> > Dave
> >
> > --
> > Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK
> >
> > --
> Marc-André Lureau
--
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK