md/raid5: use sysfs_notify_dirent_safe to avoid NULL pointer

With the module parameter 'start_dirty_degraded' set,
raid5_spare_active() previously called sysfs_notify_dirent() with a NULL
argument (rdev->sysfs_state) when a rebuild finished.

Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

1 files changed, 1 insertions, 1 deletions

diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index 316fbe79389a..9212c077095c 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -5338,7 +5338,7 @@ static int raid5_spare_active(mddev_t *mddev)
                     && !test_bit(Faulty, &tmp->rdev->flags)
                     && !test_and_set_bit(In_sync, &tmp->rdev->flags)) {
                         count++;
-                        sysfs_notify_dirent(tmp->rdev->sysfs_state);
+                        sysfs_notify_dirent_safe(tmp->rdev->sysfs_state);
                 }
         }
         spin_lock_irqsave(&conf->device_lock, flags);