2 files changed, 13 insertions, 0 deletions

diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index d505a96845c1..a3f21dc02bd8 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -15,6 +15,7 @@
 #include <linux/blkpg.h>
 #include <linux/bio.h>
 #include <linux/buffer_head.h>
+#include <linux/smp_lock.h>
 #include <linux/mempool.h>
 #include <linux/slab.h>
 #include <linux/idr.h>
@@ -338,6 +339,7 @@ static int dm_blk_open(struct block_device *bdev, fmode_t mode)
 {
 	struct mapped_device *md;
 
+	lock_kernel();
 	spin_lock(&_minor_lock);
 
 	md = bdev->bd_disk->private_data;
@@ -355,6 +357,7 @@ static int dm_blk_open(struct block_device *bdev, fmode_t mode)
 
 out:
 	spin_unlock(&_minor_lock);
+	unlock_kernel();
 
 	return md ? 0 : -ENXIO;
 }
@@ -362,8 +365,12 @@ out:
 static int dm_blk_close(struct gendisk *disk, fmode_t mode)
 {
 	struct mapped_device *md = disk->private_data;
+
+	lock_kernel();
 	atomic_dec(&md->open_count);
 	dm_put(md);
+	unlock_kernel();
+
 	return 0;
 }
 
diff --git a/drivers/md/md.c b/drivers/md/md.c
index 1893af678779..700c96edf9b2 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -36,6 +36,7 @@
 #include <linux/blkdev.h>
 #include <linux/sysctl.h>
 #include <linux/seq_file.h>
+#include <linux/smp_lock.h>
 #include <linux/buffer_head.h> /* for invalidate_bdev */
 #include <linux/poll.h>
 #include <linux/ctype.h>
@@ -5902,6 +5903,7 @@ static int md_open(struct block_device *bdev, fmode_t mode)
 	mddev_t *mddev = mddev_find(bdev->bd_dev);
 	int err;
 
+	lock_kernel();
 	if (mddev->gendisk != bdev->bd_disk) {
 		/* we are racing with mddev_put which is discarding this
 		 * bd_disk.
@@ -5910,6 +5912,7 @@ static int md_open(struct block_device *bdev, fmode_t mode)
 		/* Wait until bdev->bd_disk is definitely gone */
 		flush_scheduled_work();
 		/* Then retry the open from the top */
+		unlock_kernel();
 		return -ERESTARTSYS;
 	}
 	BUG_ON(mddev != bdev->bd_disk->private_data);
@@ -5923,6 +5926,7 @@ static int md_open(struct block_device *bdev, fmode_t mode)
 
 	check_disk_size_change(mddev->gendisk, bdev);
  out:
+	unlock_kernel();
 	return err;
 }
 
@@ -5931,8 +5935,10 @@ static int md_release(struct gendisk *disk, fmode_t mode)
  	mddev_t *mddev = disk->private_data;
 
 	BUG_ON(!mddev);
+	lock_kernel();
 	atomic_dec(&mddev->openers);
 	mddev_put(mddev);
+	unlock_kernel();
 
 	return 0;
 }