diff options
| author | Srujana Challa <schalla@marvell.com> | 2026-03-26 19:53:44 +0530 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2026-04-01 19:47:44 -0700 |
| commit | b4e5f04c58a29c499faa85d12952ca9a4faf1cb9 (patch) | |
| tree | f55984db1d7e5a726b25fd45895af57cf8b1a63c | |
| parent | d64cb81dcbd54927515a7f65e5e24affdc73c14b (diff) | |
virtio_net: clamp rss_max_key_size to NETDEV_RSS_KEY_LEN
rss_max_key_size in the virtio spec is the maximum key size supported by
the device, not a mandatory size the driver must use. Also the value 40
is a spec minimum, not a spec maximum.
The current code rejects RSS and can fail probe when the device reports a
larger rss_max_key_size than the driver buffer limit. Instead, clamp the
effective key length to min(device rss_max_key_size, NETDEV_RSS_KEY_LEN)
and keep RSS enabled.
This keeps probe working on devices that advertise larger maximum key sizes
while respecting the netdev RSS key buffer size limit.
Fixes: 3f7d9c1964fc ("virtio_net: Add hash_key_length check")
Cc: stable@vger.kernel.org
Signed-off-by: Srujana Challa <schalla@marvell.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Link: https://patch.msgid.link/20260326142344.1171317-1-schalla@marvell.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
| -rw-r--r-- | drivers/net/virtio_net.c | 20 |
1 files changed, 9 insertions, 11 deletions
diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index ab2108ee206a..c0b9bc5574e2 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -381,8 +381,6 @@ struct receive_queue { struct xdp_buff **xsk_buffs; }; -#define VIRTIO_NET_RSS_MAX_KEY_SIZE 40 - /* Control VQ buffers: protected by the rtnl lock */ struct control_buf { struct virtio_net_ctrl_hdr hdr; @@ -486,7 +484,7 @@ struct virtnet_info { /* Must be last as it ends in a flexible-array member. */ TRAILING_OVERLAP(struct virtio_net_rss_config_trailer, rss_trailer, hash_key_data, - u8 rss_hash_key_data[VIRTIO_NET_RSS_MAX_KEY_SIZE]; + u8 rss_hash_key_data[NETDEV_RSS_KEY_LEN]; ); }; static_assert(offsetof(struct virtnet_info, rss_trailer.hash_key_data) == @@ -6708,6 +6706,7 @@ static int virtnet_probe(struct virtio_device *vdev) struct virtnet_info *vi; u16 max_queue_pairs; int mtu = 0; + u16 key_sz; /* Find if host supports multiqueue/rss virtio_net device */ max_queue_pairs = 1; @@ -6842,14 +6841,13 @@ static int virtnet_probe(struct virtio_device *vdev) } if (vi->has_rss || vi->has_rss_hash_report) { - vi->rss_key_size = - virtio_cread8(vdev, offsetof(struct virtio_net_config, rss_max_key_size)); - if (vi->rss_key_size > VIRTIO_NET_RSS_MAX_KEY_SIZE) { - dev_err(&vdev->dev, "rss_max_key_size=%u exceeds the limit %u.\n", - vi->rss_key_size, VIRTIO_NET_RSS_MAX_KEY_SIZE); - err = -EINVAL; - goto free; - } + key_sz = virtio_cread8(vdev, offsetof(struct virtio_net_config, rss_max_key_size)); + + vi->rss_key_size = min_t(u16, key_sz, NETDEV_RSS_KEY_LEN); + if (key_sz > vi->rss_key_size) + dev_warn(&vdev->dev, + "rss_max_key_size=%u exceeds driver limit %u, clamping\n", + key_sz, vi->rss_key_size); vi->rss_hash_types_supported = virtio_cread32(vdev, offsetof(struct virtio_net_config, supported_hash_types)); |