On Sun, Mar 15, 2026 at 11:24:03PM +0800, Shengwen Cheng wrote: > virtqueue_reset() and virtqueue_resize() rely on the recycle callback > to release each detached unused buffer after disable_vq_and_reset(). > > As a defensive change, reject a NULL recycle callback explicitly to make > this requirement clear. Update virtqueue_disable_and_recycle() to warn > and return -EINVAL when @recycle is NULL, and update the descriptions > for virtqueue_reset() and virtqueue_resize() to document that @recycle > must not be %NULL.
I see little point in this change, sorry. > --- > drivers/virtio/virtio_ring.c | 7 +++++-- > 1 file changed, 5 insertions(+), 2 deletions(-) > > diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c > index 335692d41617..563cee634426 100644 > --- a/drivers/virtio/virtio_ring.c > +++ b/drivers/virtio/virtio_ring.c > @@ -2698,6 +2698,9 @@ static int virtqueue_disable_and_recycle(struct > virtqueue *_vq, > void *buf; > int err; > > + if (WARN_ON_ONCE(!recycle)) > + return -EINVAL; > + > if (!vq->we_own_ring) > return -EPERM; > > @@ -3311,7 +3314,7 @@ EXPORT_SYMBOL_GPL(vring_create_virtqueue_map); > * virtqueue_resize - resize the vring of vq > * @_vq: the struct virtqueue we're talking about. > * @num: new ring num > - * @recycle: callback to recycle unused buffers > + * @recycle: callback to recycle unused buffers, must not be %NULL > * @recycle_done: callback to be invoked when recycle for all unused buffers > done > * > * When it is really necessary to create a new vring, it will set the > current vq > @@ -3367,7 +3370,7 @@ EXPORT_SYMBOL_GPL(virtqueue_resize); > /** > * virtqueue_reset - detach and recycle all unused buffers > * @_vq: the struct virtqueue we're talking about. > - * @recycle: callback to recycle unused buffers > + * @recycle: callback to recycle unused buffers, must not be %NULL > * @recycle_done: callback to be invoked when recycle for all unused buffers > done > * > * Caller must ensure we don't call this with other virtqueue operations > -- > 2.34.1
