diff options
| author | Michael S. Tsirkin <mst@redhat.com> | 2014-10-15 03:52:33 +0400 |
|---|---|---|
| committer | Rusty Russell <rusty@rustcorp.com.au> | 2014-10-15 03:55:12 +0400 |
| commit | e67423c7b4f20c327de533b068907aab33720482 (patch) | |
| tree | 48c0db846c0d9ca6bea32f87adfbfebb5b385c2c | |
| parent | 1fa5b2a784dc52d929432bcc963a0bfb3a74608f (diff) | |
| download | linux-e67423c7b4f20c327de533b068907aab33720482.tar.xz | |
virtio_scsi: fix race on device removal
We cancel event work on device removal, but an interrupt
could trigger immediately after this, and queue it
again.
To fix, set a flag.
Loosely based on patch by Paolo Bonzini
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
| -rw-r--r-- | drivers/scsi/virtio_scsi.c | 11 |
1 files changed, 10 insertions, 1 deletions
diff --git a/drivers/scsi/virtio_scsi.c b/drivers/scsi/virtio_scsi.c index 29fd44a5d4dd..0227d39f45f0 100644 --- a/drivers/scsi/virtio_scsi.c +++ b/drivers/scsi/virtio_scsi.c @@ -110,6 +110,9 @@ struct virtio_scsi { /* CPU hotplug notifier */ struct notifier_block nb; + /* Protected by event_vq lock */ + bool stop_events; + struct virtio_scsi_vq ctrl_vq; struct virtio_scsi_vq event_vq; struct virtio_scsi_vq req_vqs[]; @@ -303,6 +306,11 @@ static void virtscsi_cancel_event_work(struct virtio_scsi *vscsi) { int i; + /* Stop scheduling work before calling cancel_work_sync. */ + spin_lock_irq(&vscsi->event_vq.vq_lock); + vscsi->stop_events = true; + spin_unlock_irq(&vscsi->event_vq.vq_lock); + for (i = 0; i < VIRTIO_SCSI_EVENT_LEN; i++) cancel_work_sync(&vscsi->event_list[i].work); } @@ -390,7 +398,8 @@ static void virtscsi_complete_event(struct virtio_scsi *vscsi, void *buf) { struct virtio_scsi_event_node *event_node = buf; - queue_work(system_freezable_wq, &event_node->work); + if (!vscsi->stop_events) + queue_work(system_freezable_wq, &event_node->work); } static void virtscsi_event_done(struct virtqueue *vq) |