From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Windsor Date: Tue, 2 Apr 2019 08:37:10 -0400 Subject: [Cluster-devel] [PATCH v2 1/3] dlm: check if workqueues are NULL before flushing/destroying Message-ID: <20190402123712.3241-1-dwindsor@redhat.com> List-Id: To: cluster-devel.redhat.com MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit If the DLM lowcomms stack is shut down before any DLM traffic can be generated, flush_workqueue() and destroy_workqueue() can be called on empty send and/or recv workqueues. Insert guard conditionals to only call flush_workqueue() and destroy_workqueue() on workqueues that are not NULL. Signed-off-by: David Windsor --- fs/dlm/lowcomms.c | 18 ++++++++++++------ 1 file changed, 12 insertions(+), 6 deletions(-) diff --git a/fs/dlm/lowcomms.c b/fs/dlm/lowcomms.c index a5e4a221435c..a93ebffe84b3 100644 --- a/fs/dlm/lowcomms.c +++ b/fs/dlm/lowcomms.c @@ -1630,8 +1630,10 @@ static void clean_writequeues(void) static void work_stop(void) { - destroy_workqueue(recv_workqueue); - destroy_workqueue(send_workqueue); + if (recv_workqueue) + destroy_workqueue(recv_workqueue); + if (send_workqueue) + destroy_workqueue(send_workqueue); } static int work_start(void) @@ -1691,13 +1693,17 @@ static void work_flush(void) struct hlist_node *n; struct connection *con; - flush_workqueue(recv_workqueue); - flush_workqueue(send_workqueue); + if (recv_workqueue) + flush_workqueue(recv_workqueue); + if (send_workqueue) + flush_workqueue(send_workqueue); do { ok = 1; foreach_conn(stop_conn); - flush_workqueue(recv_workqueue); - flush_workqueue(send_workqueue); + if (recv_workqueue) + flush_workqueue(recv_workqueue); + if (send_workqueue) + flush_workqueue(send_workqueue); for (i = 0; i < CONN_HASH_SIZE && ok; i++) { hlist_for_each_entry_safe(con, n, &connection_hash[i], list) { -- 2.20.1