Re: [PATCH] virtio-net: failover: add missing remove_migration_state_change_notifier()

[Laurent Vivier]

On 29/04/2021 09:26, Jason Wang wrote:
> 
> 在 2021/4/28 下午6:14, Michael S. Tsirkin 写道:
>> On Tue, Apr 27, 2021 at 03:02:34PM +0100, Dr. David Alan Gilbert wrote:
>>> * Laurent Vivier (lvivier@redhat.com) wrote:
>>>> In the failover case configuration, virtio_net_device_realize() uses an
>>>> add_migration_state_change_notifier() to add a state notifier, but this
>>>> notifier is not removed by the unrealize function when the virtio-net
>>>> card is unplugged.
>>>>
>>>> If the card is unplugged and a migration is started, the notifier is
>>>> called and as it is not valid anymore QEMU crashes.
>>>>
>>>> This patch fixes the problem by adding the
>>>> remove_migration_state_change_notifier() in virtio_net_device_unrealize().
>>>>
>>>> The problem can be reproduced with:
>>>>
>>>>    $ qemu-system-x86_64 -enable-kvm -m 1g -M q35 \
>>>>      -device pcie-root-port,slot=4,id=root1 \
>>>>      -device pcie-root-port,slot=5,id=root2 \
>>>>      -device 
>>>> virtio-net-pci,id=net1,mac=52:54:00:6f:55:cc,failover=on,bus=root1 \
>>>>      -monitor stdio disk.qcow2
>>>>    (qemu) device_del net1
>>>>    (qemu) migrate "exec:gzip -c > STATEFILE.gz"
>>>>
>>>>    Thread 1 "qemu-system-x86" received signal SIGSEGV, Segmentation fault.
>>>>    0x0000000000000000 in ?? ()
>>>>    (gdb) bt
>>>>    #0  0x0000000000000000 in  ()
>>>>    #1  0x0000555555d726d7 in notifier_list_notify (...)
>>>>        at .../util/notify.c:39
>>>>    #2  0x0000555555842c1a in migrate_fd_connect (...)
>>>>        at .../migration/migration.c:3975
>>>>    #3  0x0000555555950f7d in migration_channel_connect (...)
>>>>        error@entry=0x0) at .../migration/channel.c:107
>>>>    #4  0x0000555555910922 in exec_start_outgoing_migration (...)
>>>>        at .../migration/exec.c:42
>>>>
>>>> Reported-by: Igor Mammedov <imammedo@redhat.com>
>>>> Signed-off-by: Laurent Vivier <lvivier@redhat.com>
>>> Yep, I think that's OK.
>>>
>>>
>>> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
>> Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
>>
>> net stuff so I expect Jason will merge this ...
> 
> 
> Ok, I've queued this.

Thank you.

Any idea when the PR will be sent?

Thanks,
Laurent