git: 0ef06b5bccf4 - stable/15 - vtnet: don't provide VIRTIO_NET_HDR_F_DATA_VALID

The branch stable/15 has been updated by tuexen:

URL: https://cgit.FreeBSD.org/src/commit/?id=0ef06b5bccf43ca807e237122746dec122600157

commit 0ef06b5bccf43ca807e237122746dec122600157
Author:     Michael Tuexen <tuexen@FreeBSD.org>
AuthorDate: 2025-11-10 15:28:04 +0000
Commit:     Michael Tuexen <tuexen@FreeBSD.org>
CommitDate: 2025-11-12 08:33:33 +0000

    vtnet: don't provide VIRTIO_NET_HDR_F_DATA_VALID
    
    According to section 5.1.6.2.1 of version 1.3 of the virtio
    specification, the driver MUST NOT set VIRTIO_NET_HDR_F_DATA_VALID in
    the flags. So don't do that.
    
    Reviewed by:            Timo Völker
    Differential Revision:  https://reviews.freebsd.org/D53650
    
    (cherry picked from commit 836b3cd9d7910aff5225e9e58189067ca03fae30)
---
 sys/dev/virtio/network/if_vtnet.c | 7 +------
 1 file changed, 1 insertion(+), 6 deletions(-)

diff --git a/sys/dev/virtio/network/if_vtnet.c b/sys/dev/virtio/network/if_vtnet.c
index 471c6b3714b2..a61b0aac0bfa 100644
--- a/sys/dev/virtio/network/if_vtnet.c
+++ b/sys/dev/virtio/network/if_vtnet.c
@@ -2505,10 +2505,6 @@ vtnet_txq_offload(struct vtnet_txq *txq, struct mbuf *m,
 		hdr->csum_start = vtnet_gtoh16(sc, csum_start);
 		hdr->csum_offset = vtnet_gtoh16(sc, m->m_pkthdr.csum_data);
 		txq->vtntx_stats.vtxs_csum++;
-	} else if ((flags & (CSUM_DATA_VALID | CSUM_PSEUDO_HDR)) &&
-	           (proto == IPPROTO_TCP || proto == IPPROTO_UDP) &&
-	           (m->m_pkthdr.csum_data == 0xFFFF)) {
-		hdr->flags |= VIRTIO_NET_HDR_F_DATA_VALID;
 	}
 
 	if (flags & (CSUM_IP_TSO | CSUM_IP6_TSO)) {
@@ -2622,8 +2618,7 @@ vtnet_txq_encap(struct vtnet_txq *txq, struct mbuf **m_head, int flags)
 		m->m_flags &= ~M_VLANTAG;
 	}
 
-	if (m->m_pkthdr.csum_flags &
-	    (VTNET_CSUM_ALL_OFFLOAD | CSUM_DATA_VALID)) {
+	if (m->m_pkthdr.csum_flags & VTNET_CSUM_ALL_OFFLOAD) {
 		m = vtnet_txq_offload(txq, m, hdr);
 		if ((*m_head = m) == NULL) {
 			error = ENOBUFS;