Re: [PATCH V3 18/19] virtio_vdpa: don't warn when fail to disable vq

On 2021/2/5 下午11:24, Michael S. Tsirkin wrote:

On Mon, Jan 04, 2021 at 02:55:02PM +0800, Jason Wang wrote:

quoted

There's no guarantee that the device can disable a specific virtqueue
through set_vq_ready(). One example is the modern virtio-pci
device. So this patch removes the warning.

Signed-off-by: Jason Wang <redacted>

Do we need the read as a kind of flush though?

The problem is that PCI forbids write 0 to queue_enable. So I'm not sure what kind of flush do we need here?

Thanks

quoted

---
  drivers/virtio/virtio_vdpa.c | 3 +--
  1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/virtio/virtio_vdpa.c b/drivers/virtio/virtio_vdpa.c
index 4a9ddb44b2a7..e28acf482e0c 100644
--- a/drivers/virtio/virtio_vdpa.c
+++ b/drivers/virtio/virtio_vdpa.c

@@ -225,9 +225,8 @@ static void virtio_vdpa_del_vq(struct virtqueue *vq)
  	list_del(&info->node);
  	spin_unlock_irqrestore(&vd_dev->lock, flags);
  
-	/* Select and deactivate the queue */
+	/* Select and deactivate the queue (best effort) */
  	ops->set_vq_ready(vdpa, index, 0);
-	WARN_ON(ops->get_vq_ready(vdpa, index));
  
  	vring_del_virtqueue(vq);
  

-- 
2.25.1

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