Commit 7da2d99f authored by liujunjie's avatar liujunjie Committed by Jason Wang
Browse files

clean up callback when del virtqueue 



Before, we did not clear callback like handle_output when delete
the virtqueue which may result be segmentfault.
The scene is as follows:
1. Start a vm with multiqueue vhost-net,
2. then we write VIRTIO_PCI_GUEST_FEATURES in PCI configuration to
triger multiqueue disable in this vm which will delete the virtqueue.
In this step, the tx_bh is deleted but the callback virtio_net_handle_tx_bh
still exist.
3. Finally, we write VIRTIO_PCI_QUEUE_NOTIFY in PCI configuration to
notify the deleted virtqueue. In this way, virtio_net_handle_tx_bh
will be called and qemu will be crashed.

Although the way described above is uncommon, we had better reinforce it.

CC: qemu-stable@nongnu.org
Signed-off-by: default avatarliujunjie <liujunjie23@huawei.com>
Signed-off-by: default avatarJason Wang <jasowang@redhat.com>
parent 8e640892

hw/virtio/virtio.c

+2 −0
Original line number Diff line number Diff line
@@ -1611,6 +1611,8 @@ void virtio_del_queue(VirtIODevice *vdev, int n) 


    vdev->vq[n].vring.num = 0;

    vdev->vq[n].vring.num_default = 0;

    vdev->vq[n].handle_output = NULL;

    vdev->vq[n].handle_aio_output = NULL;

}



static void virtio_set_isr(VirtIODevice *vdev, int value)