[PATCH v3 12/25] virtio_blk: enable VQs early

From: Michael S. Tsirkin
Date: Sun Oct 12 2014 - 07:44:24 EST

virtio spec requires drivers to set DRIVER_OK before using VQs.
This is set automatically after probe returns, virtio block violated this
rule by calling add_disk, which causes the VQ to be used directly within

To fix, call virtio_enable_vqs_early before using VQs.

Signed-off-by: Michael S. Tsirkin <mst@xxxxxxxxxx>
Reviewed-by: Cornelia Huck <cornelia.huck@xxxxxxxxxx>
drivers/block/virtio_blk.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c
index 89ba8d6..46b04bf 100644
--- a/drivers/block/virtio_blk.c
+++ b/drivers/block/virtio_blk.c
@@ -719,6 +719,8 @@ static int virtblk_probe(struct virtio_device *vdev)
if (!err && opt_io_size)
blk_queue_io_opt(q, blk_size * opt_io_size);

+ virtio_enable_vqs_early(vdev);
err = device_create_file(disk_to_dev(vblk->disk), &dev_attr_serial);
if (err)

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