On 10/16/2017 01:45 AM, Leon Romanovsky wrote: > From: Parav Pandit <parav@xxxxxxxxxxxx> > > The IB/core provides address resolution service and invokes callback > handler when address resolve request completes of requester in worker > thread context. > > Such caller might allocate or free memory in callback handler > depending on the completion status to make further progress or to > terminate a connection. Most ULPs resolve route which involves > allocating route entry and path record elements in callback event handler. > > It has been noticed that WQ_MEM_RECLAIM flag should not be used for > workers that tend to allocate memory in this [1] thread discussion. > > In order to mitigate this situation, WQ_MEM_RECLAIM flag was dropped for > other such WQs in this [2] patch. > > Similar problem might arise with address resolution path, though its not > yet noticed. The ib_addr workqueue is not memory reclaim path due to its > nature of invoking callback that might allocate memory or don't free any > memory under memory pressure. > > [1] https://www.spinics.net/lists/linux-rdma/msg53239.html > [2] https://www.spinics.net/lists/linux-rdma/msg53416.html > > Fixes: f54816261c2b ("IB/addr: Remove deprecated create_singlethread_workqueue") > Fixes: 5fff41e1f89d ("IB/core: Fix race condition in resolving IP to MAC") > Signed-off-by: Parav Pandit <parav@xxxxxxxxxxxx> > Reviewed-by: Daniel Jurgens <danielj@xxxxxxxxxxxx> > Signed-off-by: Leon Romanovsky <leon@xxxxxxxxxx> This looks like a -stable patch candidate. Once accepted this should probably be queued for v4.9+. -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
