This is a note to let you know that I've just added the patch titled
RDMA/cma: Simplify DEVICE_REMOVAL for internal_id
to the 5.8-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
rdma-cma-simplify-device_removal-for-internal_id.patch
and it can be found in the queue-5.8 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 4decc6be3d3af1da5b7ab670258fc05f2c966bb5
Author: Jason Gunthorpe <jgg@xxxxxxxxxx>
Date: Thu Jul 23 10:07:04 2020 +0300
RDMA/cma: Simplify DEVICE_REMOVAL for internal_id
[ Upstream commit d54f23c09ec62670901f1a2a4712a5218522ca2b ]
cma_process_remove() triggers an unconditional rdma_destroy_id() for
internal_id's and skips the event deliver and transition through
RDMA_CM_DEVICE_REMOVAL.
This is confusing and unnecessary. internal_id always has
cma_listen_handler() as the handler, have it catch the
RDMA_CM_DEVICE_REMOVAL event and directly consume it and signal removal.
This way the FSM sequence never skips the DEVICE_REMOVAL case and the
logic in this hard to test area is simplified.
Link: https://lore.kernel.org/r/20200723070707.1771101-2-leon@xxxxxxxxxx
Signed-off-by: Leon Romanovsky <leonro@xxxxxxxxxxxx>
Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/infiniband/core/cma.c b/drivers/infiniband/core/cma.c
index c30cf5307ce3e..537eeebde5f4d 100644
--- a/drivers/infiniband/core/cma.c
+++ b/drivers/infiniband/core/cma.c
@@ -2482,6 +2482,10 @@ static int cma_listen_handler(struct rdma_cm_id *id,
{
struct rdma_id_private *id_priv = id->context;
+ /* Listening IDs are always destroyed on removal */
+ if (event->event == RDMA_CM_EVENT_DEVICE_REMOVAL)
+ return -1;
+
id->context = id_priv->id.context;
id->event_handler = id_priv->id.event_handler;
trace_cm_event_handler(id_priv, event);
@@ -4829,7 +4833,7 @@ static void cma_process_remove(struct cma_device *cma_dev)
cma_id_get(id_priv);
mutex_unlock(&lock);
- ret = id_priv->internal_id ? 1 : cma_remove_id_dev(id_priv);
+ ret = cma_remove_id_dev(id_priv);
cma_id_put(id_priv);
if (ret)
rdma_destroy_id(&id_priv->id);
