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Subject[PATCH 0/2] net/rds: RDS-TCP robustness fixes
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This patch-set contains bug fixes for state-recovery at the RDS 
layer when the underlying transport is TCP and the TCP state at one
of the endpoints is reset, e.g., due to a "modprobe -r rds_tcp" or
a reboot.

When that situation happens, the existing code does not correctly clean
up RDS socket state for stale connections, resulting in some unstable,
timing-dependant behavior on the wire, including an infinite exchange
of 3WHs back-and-forth, and a resulting potential to never converge
RDS state.

Test cases used to verify the changes in this set are:

1. Start rds client/server applications on two participating nodes,
node1 and node1. After at least one packet has been sent (to establish
the TCP connection), restart the rds_tcp module on the client, and
now resend packets. Tcpdump should show server sending a FIN for the
"old" client port, and clean connection establishment/exchange for
the new client port.

2. At the end of step 1, restart rds srever on node2, and start client on
node1, make sure using tcpdump, 'netstat -an|grep 16385' that
packets flow correctly.

Sowmini Varadhan (2):
RDS-TCP: Always create a new rds_sock for an incoming connection.
RDS-TCP: only initiate reconnect attempt on outgoing TCP socket.

net/rds/connection.c | 17 ++++++++++++++-
net/rds/tcp.c | 51 ++++++++++++++++++++++++++++++++++++++++++++++++-
net/rds/tcp.h | 5 +++-
net/rds/tcp_connect.c | 2 +-
net/rds/tcp_listen.c | 13 +++++++++++-
5 files changed, 82 insertions(+), 6 deletions(-)



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