There have been some changes upstream in FreeBSD that should be of interest here, both in STABLE 14 & 15:
- https://reviews.freebsd.org/D51475 sctp, tcp, udp: improve deferred computation of checksums
- https://reviews.freebsd.org/D51686 vtnet: fix translation between mbuf and virtio flags
[added as this thread is one of the top google searches related to freebsd tcp offload & checksum - I hope that's helpful for somebody]
- https://reviews.freebsd.org/D51475 sctp, tcp, udp: improve deferred computation of checksums
- https://reviews.freebsd.org/D51686 vtnet: fix translation between mbuf and virtio flags
[added as this thread is one of the top google searches related to freebsd tcp offload & checksum - I hope that's helpful for somebody]
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