1 files changed, 6 insertions, 2 deletions

diff --git a/drivers/md/md.c b/drivers/md/md.c
index a3019121dc57..540347c538f9 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -288,10 +288,12 @@ static int md_make_request(struct request_queue *q, struct bio *bio)
         int rv;
         int cpu;
 
-        if (mddev == NULL || mddev->pers == NULL) {
+        if (mddev == NULL || mddev->pers == NULL
+            || !mddev->ready) {
                 bio_io_error(bio);
                 return 0;
         }
+        smp_rmb(); /* Ensure implications of  'active' are visible */
         rcu_read_lock();
         if (mddev->suspended) {
                 DEFINE_WAIT(__wait);
@@ -4564,7 +4566,8 @@ int md_run(mddev_t *mddev)
         mddev->safemode_timer.data = (unsigned long) mddev;
         mddev->safemode_delay = (200 * HZ)/1000 +1; /* 200 msec delay */
         mddev->in_sync = 1;
-
+        smp_wmb();
+        mddev->ready = 1;
         list_for_each_entry(rdev, &mddev->disks, same_set)
                 if (rdev->raid_disk >= 0) {
                         char nm[20];
@@ -4725,6 +4728,7 @@ EXPORT_SYMBOL_GPL(md_stop_writes);
 
 void md_stop(mddev_t *mddev)
 {
+        mddev->ready = 0;
         mddev->pers->stop(mddev);
         if (mddev->pers->sync_request && mddev->to_remove == NULL)
                 mddev->to_remove = &md_redundancy_group;