Merge branch 'for-linus' of git://neil.brown.name/md

* 'for-linus' of git://neil.brown.name/md:
  md: fix deadlock when stopping arrays

1 files changed, 18 insertions, 12 deletions

diff --git a/drivers/md/md.c b/drivers/md/md.c
index 03b4cd0a6344..a307f87eb90e 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -214,12 +214,7 @@ static inline mddev_t *mddev_get(mddev_t *mddev)
         return mddev;
 }
 
-static void mddev_delayed_delete(struct work_struct *ws)
-{
-        mddev_t *mddev = container_of(ws, mddev_t, del_work);
-        kobject_del(&mddev->kobj);
-        kobject_put(&mddev->kobj);
-}
+static void mddev_delayed_delete(struct work_struct *ws);
 
 static void mddev_put(mddev_t *mddev)
 {
@@ -3542,6 +3537,21 @@ static struct kobj_type md_ktype = {
 
 int mdp_major = 0;
 
+static void mddev_delayed_delete(struct work_struct *ws)
+{
+        mddev_t *mddev = container_of(ws, mddev_t, del_work);
+
+        if (mddev->private == &md_redundancy_group) {
+                sysfs_remove_group(&mddev->kobj, &md_redundancy_group);
+                if (mddev->sysfs_action)
+                        sysfs_put(mddev->sysfs_action);
+                mddev->sysfs_action = NULL;
+                mddev->private = NULL;
+        }
+        kobject_del(&mddev->kobj);
+        kobject_put(&mddev->kobj);
+}
+
 static int md_alloc(dev_t dev, char *name)
 {
         static DEFINE_MUTEX(disks_mutex);
@@ -4033,13 +4043,9 @@ static int do_md_stop(mddev_t * mddev, int mode, int is_open)
                         mddev->queue->merge_bvec_fn = NULL;
                         mddev->queue->unplug_fn = NULL;
                         mddev->queue->backing_dev_info.congested_fn = NULL;
-                        if (mddev->pers->sync_request) {
-                                sysfs_remove_group(&mddev->kobj, &md_redundancy_group);
-                                if (mddev->sysfs_action)
-                                        sysfs_put(mddev->sysfs_action);
-                                mddev->sysfs_action = NULL;
-                        }
                         module_put(mddev->pers->owner);
+                        if (mddev->pers->sync_request)
+                                mddev->private = &md_redundancy_group;
                         mddev->pers = NULL;
                         /* tell userspace to handle 'inactive' */
                         sysfs_notify_dirent(mddev->sysfs_state);