diff mbox series

[PULL,09/10] virtio-net: failover: add missing remove_migration_state_change_notifier()

Message ID 1620458319-5670-10-git-send-email-jasowang@redhat.com
State New
Headers show
Series [PULL,01/10] net/tap: Added TUNSETSTEERINGEBPF code. | expand

Commit Message

Jason Wang May 8, 2021, 7:18 a.m. UTC
From: Laurent Vivier <lvivier@redhat.com>

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>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
---
 hw/net/virtio-net.c | 1 +
 1 file changed, 1 insertion(+)

Comments

Laurent Vivier May 18, 2021, 10:09 a.m. UTC | #1
Hi Jason,

do you plan to resend the PR?

Thanks,
Laurent

On 08/05/2021 09:18, Jason Wang wrote:
> From: Laurent Vivier <lvivier@redhat.com>
> 
> 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>
> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
> Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
> Signed-off-by: Laurent Vivier <lvivier@redhat.com>
> Signed-off-by: Jason Wang <jasowang@redhat.com>
> ---
>  hw/net/virtio-net.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c
> index 7ed11a3..dc71aa8 100644
> --- a/hw/net/virtio-net.c
> +++ b/hw/net/virtio-net.c
> @@ -3480,6 +3480,7 @@ static void virtio_net_device_unrealize(DeviceState *dev)
>  
>      if (n->failover) {
>          device_listener_unregister(&n->primary_listener);
> +        remove_migration_state_change_notifier(&n->migration_state);
>      }
>  
>      max_queues = n->multiqueue ? n->max_queues : 1;
>
diff mbox series

Patch

diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c
index 7ed11a3..dc71aa8 100644
--- a/hw/net/virtio-net.c
+++ b/hw/net/virtio-net.c
@@ -3480,6 +3480,7 @@  static void virtio_net_device_unrealize(DeviceState *dev)
 
     if (n->failover) {
         device_listener_unregister(&n->primary_listener);
+        remove_migration_state_change_notifier(&n->migration_state);
     }
 
     max_queues = n->multiqueue ? n->max_queues : 1;