VQs without a name specified are not valid; they are skipped in the later loop that assigns MSI-X vectors to queues, but the per_vq_vectors loop above that counts the required number of vectors previously still counted any queue with a non-NULL callback as needing a vector.
Add a check to the per_vq_vectors loop so that vectors with no name are not counted to make the two loops consistent. This prevents over-counting unnecessary vectors (e.g. for features which were not negotiated with the device).
Cc: stable@vger.kernel.org Fixes: 86a559787e6f ("virtio-balloon: VIRTIO_BALLOON_F_FREE_PAGE_HINT") Reviewed-by: Cornelia Huck cohuck@redhat.com Signed-off-by: Daniel Verkamp dverkamp@chromium.org ---
v1: https://lists.linuxfoundation.org/pipermail/virtualization/2019-December/044...
drivers/virtio/virtio_pci_common.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/virtio/virtio_pci_common.c b/drivers/virtio/virtio_pci_common.c index f2862f66c2ac..222d630c41fc 100644 --- a/drivers/virtio/virtio_pci_common.c +++ b/drivers/virtio/virtio_pci_common.c @@ -294,7 +294,7 @@ static int vp_find_vqs_msix(struct virtio_device *vdev, unsigned nvqs, /* Best option: one for change interrupt, one per vq. */ nvectors = 1; for (i = 0; i < nvqs; ++i) - if (callbacks[i]) + if (names[i] && callbacks[i]) ++nvectors; } else { /* Second best: one for change, shared for all vqs. */