[ovs-git] [openvswitch/ovs] 05b4f2: compat: Fixup ipv6 fragmentation on 4.9.135+ kernels

[gvrose8192]

  Branch: refs/heads/branch-2.6
  Home:   https://github.com/openvswitch/ovs
  Commit: 05b4f299f0f822e7605710ad3cb09a8748888e97
      https://github.com/openvswitch/ovs/commit/05b4f299f0f822e7605710ad3cb09a8748888e97
  Author: Greg Rose <gvrose8192 at gmail.com>
  Date:   2019-09-23 (Mon, 23 Sep 2019)

  Changed paths:
    M acinclude.m4
    M datapath/linux/compat/nf_conntrack_reasm.c

  Log Message:
  -----------
  compat: Fixup ipv6 fragmentation on 4.9.135+ kernels

Upstream commit 648700f76b03 ("inet: frags: use rhashtables...") changed
how ipv6 fragmentation is implemented.  This patch was backported to
the upstream stable 4.9.x kernel starting at 4.9.135.

This patch creates the compatibility layer changes required to both
compile and also operate correctly with ipv6 fragmentation on these
kernels. Check if the inet_frags 'rnd' field is present to key on
whether the upstream patch is present.  Also update Travis to the
latest 4.9 kernel release so that this patch is compile tested.

Passes Travis:
https://travis-ci.org/gvrose8192/ovs-experimental/builds/587185472

Cc: William Tu <u9012063 at gmail.com>
Cc: Yi-Hung Wei <yihung.wei at gmail.com>
Cc: Yifeng Sun <pkusunyifeng at gmail.com>
Acked-by: Yi-Hung Wei <yihung.wei at gmail.com>
Signed-off-by: Greg Rose <gvrose8192 at gmail.com>
Signed-off-by: Ben Pfaff <blp at ovn.org>