[PATCH v2 mptcp-next 0/4] mptcp: improve subflow creation on errors

[Paolo Abeni <pabeni@redhat.com>]

This iteration just addresses a compile warning spotted by the
CI.

Currently when a subflow connection fails - either the TCP
connection is reset by the peer, or the MPJ handshake never
completes - the in kernel PM don't perform any further action.
Notably no additional subflow creation is attempted.

This series is aimed at improving the in-kernel path manager
behavior in the above scenario:
- each endpoint is used only once per connection (patch 2/4)
- on failure we try to move to the next subflow, if any
  (patch 3/4)

The first patch is minor cleanup, and the last patch adds
specific self-tests.

This should address/close:
https://github.com/multipath-tcp/mptcp_net-next/issues/235
https://github.com/multipath-tcp/mptcp_net-next/issues/242

Paolo Abeni (4):
  mptcp: clean-up MPJ option writing.
  mptcp: keep track of used local endpoint
  mptcp: do not block subflows creation on errors
  selftests: mptcp: add tests for subflow creation failure

 net/mptcp/options.c                           | 65 ++++++++++++-------
 net/mptcp/pm.c                                | 28 +++++++-
 net/mptcp/pm_netlink.c                        |  8 ++-
 net/mptcp/protocol.c                          |  6 ++
 net/mptcp/protocol.h                          |  5 +-
 net/mptcp/subflow.c                           |  5 +-
 tools/testing/selftests/net/mptcp/config      |  1 +
 .../testing/selftests/net/mptcp/mptcp_join.sh | 65 ++++++++++++++++++-
 8 files changed, 153 insertions(+), 30 deletions(-)

-- 
2.33.1