[PATCH 3.13 035/259] virtio-scsi: avoid cancelling uninitialized work items

From: Kamal Mostafa
Date: Fri Aug 08 2014 - 18:19:22 EST


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

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

From: Paolo Bonzini <pbonzini@xxxxxxxxxx>

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@xxxxxxxxxx>
Reviewed-by: Stefan Hajnoczi <stefanha@xxxxxxxxxx>
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
Signed-off-by: Kamal Mostafa <kamal@xxxxxxxxxxxxx>
---
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 db3b494..a91a135 100644
--- a/drivers/scsi/virtio_scsi.c
+++ b/drivers/scsi/virtio_scsi.c
@@ -291,6 +291,8 @@ 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)
{
@@ -298,6 +300,7 @@ 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);
@@ -415,7 +418,6 @@ 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

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