Message ID | 1375102920-18817-5-git-send-email-stefanha@redhat.com |
---|---|
State | New |
Headers | show |
diff --git a/hw/block/dataplane/virtio-blk.c b/hw/block/dataplane/virtio-blk.c index 63c3ffa..411becc 100644 --- a/hw/block/dataplane/virtio-blk.c +++ b/hw/block/dataplane/virtio-blk.c @@ -415,6 +415,14 @@ bool virtio_blk_data_plane_create(VirtIODevice *vdev, VirtIOBlkConf *blk, return false; } + /* If dataplane is (re-)enabled while the guest is running there could be + * block jobs that can conflict. + */ + if (bdrv_in_use(blk->conf.bs)) { + error_report("cannot start dataplane thread while device is in use"); + return false; + } + fd = raw_get_aio_fd(blk->conf.bs); if (fd < 0) { error_report("drive is incompatible with x-data-plane, "
Dataplane must check whether a block device is in use before launching the dataplane thread. This is necessary since the thread does not synchronize with the main loop and I/O requests could cause corruption. One example is when a drive is added and a block job is started before hotplugging the virtio-blk-pci adapter. In this case we must not use dataplane mode. Cc: qemu-stable@nongnu.org Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> --- hw/block/dataplane/virtio-blk.c | 8 ++++++++ 1 file changed, 8 insertions(+)