On Thu, Mar 25, 2021 at 1:24 PM Paolo Abeni [off-list ref] wrote:
After the previous patch, the stack can do L4 UDP aggregation
on top of a UDP tunnel.
In such scenario, udp{4,6}_gro_complete will be called twice. This function
will enter its is_flist branch immediately, even though that is only
correct on the second call, as GSO_FRAGLIST is only relevant for the
inner packet.
Instead, we need to try first UDP tunnel-based aggregation, if the GRO
packet requires that.
This patch changes udp{4,6}_gro_complete to skip the frag list processing
when while encap_mark == 1, identifying processing of the outer tunnel
header.
Additionally, clears the field in udp_gro_complete() so that we can enter
the frag list path on the next round, for the inner header.
v1 -> v2:
- hopefully clarified the commit message
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>