tcm_vhost: Initialize vq->last_used_idx when set endpoint
authorAsias He <asias@redhat.com>
Wed, 3 Apr 2013 06:17:38 +0000 (14:17 +0800)
committerNicholas Bellinger <nab@linux-iscsi.org>
Mon, 8 Apr 2013 21:09:54 +0000 (14:09 -0700)
commitdfd5d5692c7ddf27380511b80a3dc590acfc4eee
tree482d5438c0e3f9ca191ad8ce1b9f447c15ee72cf
parent4f7f46d32c9875004fae1d57ae3c02cc2e6cd6a3
tcm_vhost: Initialize vq->last_used_idx when set endpoint

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@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
drivers/vhost/tcm_vhost.c