Michael Tuexen d4697a6b56 vtnet: fix TSO for TCP/IPv6
The decision whether a TCP packet is sent over IPv4 or IPv6 was
based on ethertype, which works correctly. In D27926 the criteria
was changed to checking if the CSUM_IP_TSO flag is set in the
csum-flags and then considering it to be TCP/IPv4.
However, the TCP stack sets the flag to CSUM_TSO for IPv4 and IPv6,
where CSUM_TSO is defined as CSUM_IP_TSO|CSUM_IP6_TSO.
Therefore TCP/IPv6 packets gets mis-classified as TCP/IPv4,
which breaks TSO for TCP/IPv6.
This patch bases the check again on the ethertype.
This fix will be MFC instantly as discussed with re(gjb).

MFC after:		instantly
PR:			254366
Sponsored by:		Netflix, Inc.
Differential Revision:	https://reviews.freebsd.org/D29331
2021-03-18 21:32:20 +01:00
..
2021-03-18 21:32:20 +01:00