[PATCH 3.11 066/128] virtio-scsi: avoid cancelling uninitialized work items

[Luis Henriques]

3.11.10.14 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: Paolo Bonzini <pbonzini at redhat.com>

commit cdda0e5acbb78f7b777049f8c27899e5c5bb368f upstream.

Calling the workqueue interface on uninitialized work items isn't a
good idea even if they're zeroed. It's not failing catastrophically only
through happy accidents.

Signed-off-by: Paolo Bonzini <pbonzini at redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha at redhat.com>
Signed-off-by: Christoph Hellwig <hch at lst.de>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 drivers/scsi/virtio_scsi.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/scsi/virtio_scsi.c b/drivers/scsi/virtio_scsi.c
index 95a5d73e675c..57c39e1e6681 100644
--- a/drivers/scsi/virtio_scsi.c
+++ b/drivers/scsi/virtio_scsi.c
@@ -288,6 +288,8 @@ static void virtscsi_ctrl_done(struct virtqueue *vq)
 	virtscsi_vq_done(vscsi, &vscsi->ctrl_vq, virtscsi_complete_free);
 };
 
+static void virtscsi_handle_event(struct work_struct *work);
+
 static int virtscsi_kick_event(struct virtio_scsi *vscsi,
 			       struct virtio_scsi_event_node *event_node)
 {
@@ -295,6 +297,7 @@ static int virtscsi_kick_event(struct virtio_scsi *vscsi,
 	struct scatterlist sg;
 	unsigned long flags;
 
+	INIT_WORK(&event_node->work, virtscsi_handle_event);
 	sg_init_one(&sg, &event_node->event, sizeof(struct virtio_scsi_event));
 
 	spin_lock_irqsave(&vscsi->event_vq.vq_lock, flags);
@@ -412,7 +415,6 @@ static void virtscsi_complete_event(struct virtio_scsi *vscsi, void *buf)
 {
 	struct virtio_scsi_event_node *event_node = buf;
 
-	INIT_WORK(&event_node->work, virtscsi_handle_event);
 	schedule_work(&event_node->work);
 }
 
-- 
1.9.1