3.16.62-rc1 review patch. If anyone has any objections, please let me know.
------------------ From: Denis Drozdov <[email protected]> commit 75da96067ade4e7854379ec2f7834f3497652b1a upstream. The change of ipoib_ah data structure with adding "valid" flag and checks of ah->valid in ipoib_start_xmit affected multicast packet flow. Since the multicast flow doesn't invoke path_rec_start, "ah->valid" flag remains unset, so that ipoib_start_xmit end up with neigh_refresh_path instead of sending the packet using neigh. "ah->valid" has to be set in multicast send flow. As a result IPoIB starts sending packets via neigh immediately and eliminates 60sec delay of neigh keep alive interval. The typical example of this issue are two sequential arpings: arping 11.134.208.9 -> got response (mcast_send) arping 11.134.208.9 -> no response (ah->valid = 0) Fixes: fa9391dbad4b ("RDMA/ipoib: Update paths on CLIENT_REREG/SM_CHANGE events") Signed-off-by: Denis Drozdov <[email protected]> Reviewed-by: Erez Shitrit <[email protected]> Reviewed-by: Feras Daoud <[email protected]> Signed-off-by: Leon Romanovsky <[email protected]> Signed-off-by: Jason Gunthorpe <[email protected]> Signed-off-by: Ben Hutchings <[email protected]> --- drivers/infiniband/ulp/ipoib/ipoib_multicast.c | 1 + 1 file changed, 1 insertion(+) --- a/drivers/infiniband/ulp/ipoib/ipoib_multicast.c +++ b/drivers/infiniband/ulp/ipoib/ipoib_multicast.c @@ -734,6 +734,7 @@ out: if (neigh && list_empty(&neigh->list)) { kref_get(&mcast->ah->ref); neigh->ah = mcast->ah; + neigh->ah->valid = 1; list_add_tail(&neigh->list, &mcast->neigh_list); } }
