[PATCH net v2 2/3] virtio-net: remove redundant truesize check with PAGE_SIZE
From: Bui Quang Minh <hidden>
Date: 2025-06-30 14:42:56
Also in:
bpf, lkml, virtualization
Subsystem:
networking drivers, the rest, virtio net driver · Maintainers:
Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds, "Michael S. Tsirkin", Jason Wang
The truesize is guaranteed not to exceed PAGE_SIZE in get_mergeable_buf_len(). It is saved in mergeable context, which is not changeable by the host side, so the check in receive path is quite redundant. Acked-by: Jason Wang <redacted> Signed-off-by: Bui Quang Minh <redacted> --- drivers/net/virtio_net.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-)
diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 31661bcb3932..535a4534c27f 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c@@ -2157,9 +2157,9 @@ static int virtnet_build_xdp_buff_mrg(struct net_device *dev, { struct virtio_net_hdr_mrg_rxbuf *hdr = buf; unsigned int headroom, tailroom, room; - unsigned int truesize, cur_frag_size; struct skb_shared_info *shinfo; unsigned int xdp_frags_truesz = 0; + unsigned int truesize; struct page *page; skb_frag_t *frag; int offset;
@@ -2207,9 +2207,8 @@ static int virtnet_build_xdp_buff_mrg(struct net_device *dev, tailroom = headroom ? sizeof(struct skb_shared_info) : 0; room = SKB_DATA_ALIGN(headroom + tailroom); - cur_frag_size = truesize; - xdp_frags_truesz += cur_frag_size; - if (unlikely(len > truesize - room || cur_frag_size > PAGE_SIZE)) { + xdp_frags_truesz += truesize; + if (unlikely(len > truesize - room)) { put_page(page); pr_debug("%s: rx error: len %u exceeds truesize %lu\n", dev->name, len, (unsigned long)(truesize - room));
--
2.43.0