RDMA/cma: Fix hang when cma_netevent_callback fails to queue_work
authorJack Morgenstein <jackm@nvidia.com>
Wed, 21 May 2025 11:36:02 +0000 (14:36 +0300)
committerJason Gunthorpe <jgg@nvidia.com>
Mon, 26 May 2025 18:36:46 +0000 (15:36 -0300)
commit92a251c3df8ea1991cd9fe00f1ab0cfce18d7711
treef8c63aeabffa72189af9ef5d0ddd1678d1e584a2
parentef2233850edc4cc0d5fc6136fcdb004a1ddfa7db
RDMA/cma: Fix hang when cma_netevent_callback fails to queue_work

The cited commit fixed a crash when cma_netevent_callback was called for
a cma_id while work on that id from a previous call had not yet started.
The work item was re-initialized in the second call, which corrupted the
work item currently in the work queue.

However, it left a problem when queue_work fails (because the item is
still pending in the work queue from a previous call). In this case,
cma_id_put (which is called in the work handler) is therefore not
called. This results in a userspace process hang (zombie process).

Fix this by calling cma_id_put() if queue_work fails.

Fixes: 45f5dcdd0497 ("RDMA/cma: Fix workqueue crash in cma_netevent_work_handler")
Link: https://patch.msgid.link/r/4f3640b501e48d0166f312a64fdadf72b059bd04.1747827103.git.leon@kernel.org
Signed-off-by: Jack Morgenstein <jackm@nvidia.com>
Signed-off-by: Feng Liu <feliu@nvidia.com>
Reviewed-by: Vlad Dumitrescu <vdumitrescu@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Reviewed-by: Sharath Srinivasan <sharath.srinivasan@oracle.com>
Reviewed-by: Kalesh AP <kalesh-anakkur.purayil@broadcom.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
drivers/infiniband/core/cma.c