diff options
author | Gerd Hoffmann <kraxel@redhat.com> | 2018-04-03 12:59:04 +0300 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-05-02 01:13:05 +0300 |
commit | 97f54c13b6aaa49eeb9688e851d1ff955f45f5c3 (patch) | |
tree | 555bca933a49b4c0062e302d0b26f8b38b37e54e | |
parent | 47cb14192bcbba3f15b1c3561e05e084e56fdef6 (diff) | |
download | linux-97f54c13b6aaa49eeb9688e851d1ff955f45f5c3.tar.xz |
drm/virtio: fix vq wait_event condition
commit d02d270014f70dcab0117776b81a37b6fca745ae upstream.
Wait until we have enough space in the virt queue to actually queue up
our request. Avoids the guest spinning in case we have a non-zero
amount of free entries but not enough for the request.
Cc: stable@vger.kernel.org
Reported-by: Alain Magloire <amagloire@blackberry.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Dave Airlie <airlied@redhat.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20180403095904.11152-1-kraxel@redhat.com
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r-- | drivers/gpu/drm/virtio/virtgpu_vq.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/drivers/gpu/drm/virtio/virtgpu_vq.c b/drivers/gpu/drm/virtio/virtgpu_vq.c index 5a0f8a745b9d..52436b3c01bb 100644 --- a/drivers/gpu/drm/virtio/virtgpu_vq.c +++ b/drivers/gpu/drm/virtio/virtgpu_vq.c @@ -324,7 +324,7 @@ retry: ret = virtqueue_add_sgs(vq, sgs, outcnt, incnt, vbuf, GFP_ATOMIC); if (ret == -ENOSPC) { spin_unlock(&vgdev->ctrlq.qlock); - wait_event(vgdev->ctrlq.ack_queue, vq->num_free); + wait_event(vgdev->ctrlq.ack_queue, vq->num_free >= outcnt + incnt); spin_lock(&vgdev->ctrlq.qlock); goto retry; } else { @@ -399,7 +399,7 @@ retry: ret = virtqueue_add_sgs(vq, sgs, outcnt, 0, vbuf, GFP_ATOMIC); if (ret == -ENOSPC) { spin_unlock(&vgdev->cursorq.qlock); - wait_event(vgdev->cursorq.ack_queue, vq->num_free); + wait_event(vgdev->cursorq.ack_queue, vq->num_free >= outcnt); spin_lock(&vgdev->cursorq.qlock); goto retry; } else { |