On Sat, Mar 22, 2025 at 03:47:17PM +0900, Akihiko Odaki wrote:
> virtio-net uses the max_tx_vq field of struct virtio_net_rss_config to
> determine the number of queue pairs and emits an error message saying
> "Can't get queue_pairs". However, the field tells only about tx.
>
> Examine unclassified_queue and indirection_table to determine the number
> of queues required for rx, and correct the name of field in the error
> message, clarifying its correct semantics.
>
> Fixes: 590790297c0d ("virtio-net: implement RSS configuration command")
> Signed-off-by: Akihiko Odaki <akihiko.od...@daynix.com>
> ---
Breaks CI:
https://gitlab.com/mstredhat/qemu/-/jobs/10199709161
../hw/net/virtio-net.c:1463:48: error: taking address of packed member 'us' of
class or structure 'struct (unnamed at ../hw/net/virtio-net.c:1392:5)' may
result in an unaligned pointer value [-Werror,-Waddress-of-packed-member]
1463 | queue_pairs = MAX(virtio_lduw_p(vdev, &temp.us),
| ^~~~~~~
../include/qemu/osdep.h:419:19: note: expanded from macro 'MAX'
419 | MAX_INTERNAL((a), (b), MAKE_IDENTIFIER(_a), MAKE_IDENTIFIER(_b))
| ^
../include/qemu/osdep.h:414:21: note: expanded from macro 'MAX_INTERNAL'
414 | typeof(1 ? (a) : (b)) _a = (a), _b = (b); \
| ^
1 error generated.
> Changes in v2:
> - Handled unclassified_queue too.
> - Added a Fixes: tag.
> - Link to v1:
> https://lore.kernel.org/qemu-devel/20250321-vq-v1-1-6d6d285e5...@daynix.com
> ---
> hw/net/virtio-net.c | 26 ++++++++++++++++----------
> 1 file changed, 16 insertions(+), 10 deletions(-)
>
> diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c
> index de87cfadffe1..afc6b82f13c9 100644
> --- a/hw/net/virtio-net.c
> +++ b/hw/net/virtio-net.c
> @@ -1450,23 +1450,29 @@ static uint16_t virtio_net_handle_rss(VirtIONet *n,
> err_value = (uint32_t)s;
> goto error;
> }
> - for (i = 0; i < n->rss_data.indirections_len; ++i) {
> - uint16_t val = n->rss_data.indirections_table[i];
> - n->rss_data.indirections_table[i] = virtio_lduw_p(vdev, &val);
> - }
> offset += size_get;
> size_get = sizeof(temp);
> s = iov_to_buf(iov, iov_cnt, offset, &temp, size_get);
> if (s != size_get) {
> - err_msg = "Can't get queue_pairs";
> + err_msg = "Can't get max_tx_vq";
> err_value = (uint32_t)s;
> goto error;
> }
> - queue_pairs = do_rss ? virtio_lduw_p(vdev, &temp.us) :
> n->curr_queue_pairs;
> - if (queue_pairs == 0 || queue_pairs > n->max_queue_pairs) {
> - err_msg = "Invalid number of queue_pairs";
> - err_value = queue_pairs;
> - goto error;
> + if (do_rss) {
> + queue_pairs = MAX(virtio_lduw_p(vdev, &temp.us),
> + n->rss_data.default_queue);
> + for (i = 0; i < n->rss_data.indirections_len; ++i) {
> + uint16_t val = n->rss_data.indirections_table[i];
> + n->rss_data.indirections_table[i] = virtio_lduw_p(vdev, &val);
> + queue_pairs = MAX(queue_pairs,
> n->rss_data.indirections_table[i]);
> + }
> + if (queue_pairs == 0 || queue_pairs > n->max_queue_pairs) {
> + err_msg = "Invalid number of queue_pairs";
> + err_value = queue_pairs;
> + goto error;
> + }
> + } else {
> + queue_pairs = n->curr_queue_pairs;
> }
> if (temp.b > VIRTIO_NET_RSS_MAX_KEY_SIZE) {
> err_msg = "Invalid key size";
>
> ---
> base-commit: 825b96dbcee23d134b691fc75618b59c5f53da32
> change-id: 20250321-vq-87aff4f531bf
>
> Best regards,
> --
> Akihiko Odaki <akihiko.od...@daynix.com>
