Patch "vhost_vdpa: tell vqs about the negotiated" has been added to the 6.1-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    vhost_vdpa: tell vqs about the negotiated

to the 6.1-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     vhost_vdpa-tell-vqs-about-the-negotiated.patch
and it can be found in the queue-6.1 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit 8f98c064799fb529e06323d37a24675d92920d16
Author: Shannon Nelson <shannon.nelson@xxxxxxx>
Date:   Mon Apr 24 15:50:29 2023 -0700

    vhost_vdpa: tell vqs about the negotiated
    
    [ Upstream commit 376daf317753ccb6b1ecbdece66018f7f6313a7f ]
    
    As is done in the net, iscsi, and vsock vhost support, let the vdpa vqs
    know about the features that have been negotiated.  This allows vhost
    to more safely make decisions based on the features, such as when using
    PACKED vs split queues.
    
    Signed-off-by: Shannon Nelson <shannon.nelson@xxxxxxx>
    Acked-by: Jason Wang <jasowang@xxxxxxxxxx>
    Message-Id: <20230424225031.18947-2-shannon.nelson@xxxxxxx>
    Signed-off-by: Michael S. Tsirkin <mst@xxxxxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c
index d591f77961aa8..31a156669a531 100644
--- a/drivers/vhost/vdpa.c
+++ b/drivers/vhost/vdpa.c
@@ -377,7 +377,10 @@ static long vhost_vdpa_set_features(struct vhost_vdpa *v, u64 __user *featurep)
 {
 	struct vdpa_device *vdpa = v->vdpa;
 	const struct vdpa_config_ops *ops = vdpa->config;
+	struct vhost_dev *d = &v->vdev;
+	u64 actual_features;
 	u64 features;
+	int i;
 
 	/*
 	 * It's not allowed to change the features after they have
@@ -392,6 +395,16 @@ static long vhost_vdpa_set_features(struct vhost_vdpa *v, u64 __user *featurep)
 	if (vdpa_set_features(vdpa, features))
 		return -EINVAL;
 
+	/* let the vqs know what has been configured */
+	actual_features = ops->get_driver_features(vdpa);
+	for (i = 0; i < d->nvqs; ++i) {
+		struct vhost_virtqueue *vq = d->vqs[i];
+
+		mutex_lock(&vq->mutex);
+		vq->acked_features = actual_features;
+		mutex_unlock(&vq->mutex);
+	}
+
 	return 0;
 }