On Mon, 2013-03-25 at 13:16 +0200, Michael S. Tsirkin wrote: > On Fri, Mar 22, 2013 at 10:52:28AM +0800, Asias He wrote: > > This patch fixes guest hang when booting seabios and guest. > > > > [ 0.576238] scsi0 : Virtio SCSI HBA > > [ 0.616754] virtio_scsi virtio1: request:id 0 is not a head! > > > > vq->last_used_idx is initialized only when /dev/vhost-scsi is > > opened or closed. > > > > vhost_scsi_open -> vhost_dev_init() -> vhost_vq_reset() > > vhost_scsi_release() -> vhost_dev_cleanup -> vhost_vq_reset() > > > > So, when guest talks to tcm_vhost after seabios does, vq->last_used_idx > > still contains the old valule for seabios. This confuses guest. > > > > Fix this by calling vhost_init_used() to init vq->last_used_idx when > > we set endpoint. > > > > Signed-off-by: Asias He <asias@xxxxxxxxxx> > > Good catch, thanks. > > Acked-by: Michael S. Tsirkin <mst@xxxxxxxxxx> > > Nicholas can you pick this one up for 3.9 please? > Just a heads up that this needs PATCH 1/2 as vhost_init_used() expects vq->private_data to already have been set.. Can you take a another look at the first patch as a v3.9 item..? Both are required in order for Asias's seabios changes to work. Thanks, --nab > > --- > > drivers/vhost/tcm_vhost.c | 1 + > > 1 file changed, 1 insertion(+) > > > > diff --git a/drivers/vhost/tcm_vhost.c b/drivers/vhost/tcm_vhost.c > > index 099feef..0524267 100644 > > --- a/drivers/vhost/tcm_vhost.c > > +++ b/drivers/vhost/tcm_vhost.c > > @@ -848,6 +848,7 @@ static int vhost_scsi_set_endpoint( > > /* Flushing the vhost_work acts as synchronize_rcu */ > > mutex_lock(&vq->mutex); > > rcu_assign_pointer(vq->private_data, vs); > > + vhost_init_used(vq); > > mutex_unlock(&vq->mutex); > > } > > ret = 0; > > -- > > 1.8.1.4 > -- > To unsubscribe from this list: send the line "unsubscribe target-devel" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
