[PATCHv2 1/3] nvme-multipath: fix leak on try_module_get failure

[Keith Busch]

From: Keith Busch <kbusch at kernel.org>

We need to fall back to the synchronous removal if we can't get a
reference on the module needed for the deferred removal.

Fixes: 62188639ec16 ("nvme-multipath: introduce delayed removal of the multipath head node")
Reviewed-by: Nilay Shroff <nilay at linux.ibm.com>
Reviewed-by: John Garry <john.g.garry at oracle.com>
Reviewed-by: Christoph Hellwig <hch at lst.de>
Signed-off-by: Keith Busch <kbusch at kernel.org>
---
 drivers/nvme/host/multipath.c | 12 +++++-------
 1 file changed, 5 insertions(+), 7 deletions(-)

diff --git a/drivers/nvme/host/multipath.c b/drivers/nvme/host/multipath.c
index bfcc5904e6a26..fc6800a9f7f94 100644
--- a/drivers/nvme/host/multipath.c
+++ b/drivers/nvme/host/multipath.c
@@ -1310,13 +1310,11 @@ void nvme_mpath_remove_disk(struct nvme_ns_head *head)
 	if (!list_empty(&head->list))
 		goto out;
 
-	if (head->delayed_removal_secs) {
-		/*
-		 * Ensure that no one could remove this module while the head
-		 * remove work is pending.
-		 */
-		if (!try_module_get(THIS_MODULE))
-			goto out;
+	/*
+	 * Ensure that no one could remove this module while the head
+	 * remove work is pending.
+	 */
+	if (head->delayed_removal_secs && try_module_get(THIS_MODULE)) {
 		mod_delayed_work(nvme_wq, &head->remove_work,
 				head->delayed_removal_secs * HZ);
 	} else {
-- 
2.47.3