Re: Fwd: Re: [PATCH v3 3/6] virtio-scsi: avoid cancelling uninitialized work items

From: Stefan Hajnoczi
Date: Wed Jun 11 2014 - 09:19:46 EST


On Wed, Jun 11, 2014 at 02:53:46PM +0200, Paolo Bonzini wrote:
> -------- Messaggio originale --------
> From: Christoph Hellwig <hch@xxxxxxxxxxxxx>
> To: Paolo Bonzini <pbonzini@xxxxxxxxxx>
> Cc: linux-kernel@xxxxxxxxxxxxxxx, linux-scsi@xxxxxxxxxxxxxxx, hch@xxxxxx, JBottomley@xxxxxxxxxxxxx, venkateshs@xxxxxxxxxx
> Subject: Re: [PATCH v3 3/6] virtio-scsi: avoid cancelling uninitialized work items
> Message-ID: <20140611124731.GA16990@xxxxxxxxxxxxx>
> In-Reply-To: <1401881699-1456-4-git-send-email-pbonzini@xxxxxxxxxx>
>
> Can I get a second review on this one from anyone?

Reviewed-by: Stefan Hajnoczi <stefanha@xxxxxxxxxx>

> On Wed, Jun 04, 2014 at 01:34:56PM +0200, Paolo Bonzini wrote:
> > 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>
> > ---
> > 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 f0b4cdbfceb0..d66c4ee2c774 100644
> > --- a/drivers/scsi/virtio_scsi.c
> > +++ b/drivers/scsi/virtio_scsi.c
> > @@ -253,6 +253,8 @@ 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)
> > {
> > @@ -260,6 +262,7 @@ 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);
> > @@ -377,7 +380,6 @@ 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);
> > }
> >
> > --
> > 1.8.3.1
>

Attachment: pgp4PqHv13vfK.pgp
Description: PGP signature