[PATCH 6/6] xfs: lock the healthmon when inserting unmount event

From: Darrick J. Wong <[email protected]>

LOLLM complains that xfs_healthmon_unmount does an unlocked insert of
the unmount event into the health monitor's event list.  Fix that.

Cc: <[email protected]> # v7.0
Fixes: 25ca57fa3624ca ("xfs: convey filesystem unmount events to the health monitor")
Signed-off-by: "Darrick J. Wong" <[email protected]>
Assisted-by: LOLLM # finding obvious bugs
---
 fs/xfs/xfs_healthmon.c |    2 ++
 1 file changed, 2 insertions(+)


diff --git a/fs/xfs/xfs_healthmon.c b/fs/xfs/xfs_healthmon.c
index 4521ffdab9f1ae..d8b95af33a3e9f 100644
--- a/fs/xfs/xfs_healthmon.c
+++ b/fs/xfs/xfs_healthmon.c
@@ -415,8 +415,10 @@ xfs_healthmon_unmount(
 	 * There's nothing actionable for userspace after an unmount.  Once
 	 * we've inserted the unmount event, hm no longer owns that event.
 	 */
+	mutex_lock(&hm->lock);
 	__xfs_healthmon_insert(hm, hm->unmount_event);
 	hm->unmount_event = NULL;
+	mutex_unlock(&hm->lock);
 
 	xfs_healthmon_detach(hm);
 	xfs_healthmon_put(hm);