This is a note to let you know that I've just added the patch titled virtio_net: Support dynamic rss indirection table size to the 6.11-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: virtio_net-support-dynamic-rss-indirection-table-siz.patch and it can be found in the queue-6.11 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 26f1099ae03e2a348ce4fc3f96f2cc01923a4cd8 Author: Philo Lu <lulie@xxxxxxxxxxxxxxxxx> Date: Mon Nov 4 16:57:03 2024 +0800 virtio_net: Support dynamic rss indirection table size [ Upstream commit 86a48a00efdf61197b6658e52c6140463eb313dc ] When reading/writing virtio_net_ctrl_rss, we get the indirection table size from vi->rss_indir_table_size, which is initialized in virtnet_probe(). However, the actual size of indirection_table was set as VIRTIO_NET_RSS_MAX_TABLE_LEN=128. This collision may cause issues if the vi->rss_indir_table_size exceeds 128. This patch instead uses dynamic indirection table, allocated with vi->rss after vi->rss_indir_table_size initialized. And free it in virtnet_remove(). In virtnet_commit_rss_command(), sgs for rss is initialized differently with hash_report. So indirection_table is not used if !vi->has_rss, and then we don't need to alloc indirection_table for hash_report only uses. Fixes: c7114b1249fa ("drivers/net/virtio_net: Added basic RSS support.") Signed-off-by: Philo Lu <lulie@xxxxxxxxxxxxxxxxx> Signed-off-by: Xuan Zhuo <xuanzhuo@xxxxxxxxxxxxxxxxx> Acked-by: Joe Damato <jdamato@xxxxxxxxxx> Acked-by: Michael S. Tsirkin <mst@xxxxxxxxxx> Signed-off-by: Paolo Abeni <pabeni@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index 792e9eadbfc3d..4b507007d242b 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -368,15 +368,16 @@ struct receive_queue { * because table sizes may be differ according to the device configuration. */ #define VIRTIO_NET_RSS_MAX_KEY_SIZE 40 -#define VIRTIO_NET_RSS_MAX_TABLE_LEN 128 struct virtio_net_ctrl_rss { u32 hash_types; u16 indirection_table_mask; u16 unclassified_queue; - u16 indirection_table[VIRTIO_NET_RSS_MAX_TABLE_LEN]; + u16 hash_cfg_reserved; /* for HASH_CONFIG (see virtio_net_hash_config for details) */ u16 max_tx_vq; u8 hash_key_length; u8 key[VIRTIO_NET_RSS_MAX_KEY_SIZE]; + + u16 *indirection_table; }; /* Control VQ buffers: protected by the rtnl lock */ @@ -512,6 +513,25 @@ static struct sk_buff *virtnet_skb_append_frag(struct sk_buff *head_skb, struct page *page, void *buf, int len, int truesize); +static int rss_indirection_table_alloc(struct virtio_net_ctrl_rss *rss, u16 indir_table_size) +{ + if (!indir_table_size) { + rss->indirection_table = NULL; + return 0; + } + + rss->indirection_table = kmalloc_array(indir_table_size, sizeof(u16), GFP_KERNEL); + if (!rss->indirection_table) + return -ENOMEM; + + return 0; +} + +static void rss_indirection_table_free(struct virtio_net_ctrl_rss *rss) +{ + kfree(rss->indirection_table); +} + static bool is_xdp_frame(void *ptr) { return (unsigned long)ptr & VIRTIO_XDP_FLAG; @@ -3828,11 +3848,15 @@ static bool virtnet_commit_rss_command(struct virtnet_info *vi) /* prepare sgs */ sg_init_table(sgs, 4); - sg_buf_size = offsetof(struct virtio_net_ctrl_rss, indirection_table); + sg_buf_size = offsetof(struct virtio_net_ctrl_rss, hash_cfg_reserved); sg_set_buf(&sgs[0], &vi->rss, sg_buf_size); - sg_buf_size = sizeof(uint16_t) * (vi->rss.indirection_table_mask + 1); - sg_set_buf(&sgs[1], vi->rss.indirection_table, sg_buf_size); + if (vi->has_rss) { + sg_buf_size = sizeof(uint16_t) * vi->rss_indir_table_size; + sg_set_buf(&sgs[1], vi->rss.indirection_table, sg_buf_size); + } else { + sg_set_buf(&sgs[1], &vi->rss.hash_cfg_reserved, sizeof(uint16_t)); + } sg_buf_size = offsetof(struct virtio_net_ctrl_rss, key) - offsetof(struct virtio_net_ctrl_rss, max_tx_vq); @@ -6420,6 +6444,9 @@ static int virtnet_probe(struct virtio_device *vdev) virtio_cread16(vdev, offsetof(struct virtio_net_config, rss_max_indirection_table_length)); } + err = rss_indirection_table_alloc(&vi->rss, vi->rss_indir_table_size); + if (err) + goto free; if (vi->has_rss || vi->has_rss_hash_report) { vi->rss_key_size = @@ -6674,6 +6701,8 @@ static void virtnet_remove(struct virtio_device *vdev) remove_vq_common(vi); + rss_indirection_table_free(&vi->rss); + free_netdev(vi->dev); }