diff --git a/fs/block_dev.c b/fs/block_dev.c
index 7022ddc..95acbd2 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -2207,6 +2207,7 @@ void iterate_bdevs(void (*func)(struct block_device *, void *), void *arg)
 	spin_lock(&blockdev_superblock->s_inode_list_lock);
 	list_for_each_entry(inode, &blockdev_superblock->s_inodes, i_sb_list) {
 		struct address_space *mapping = inode->i_mapping;
+		struct block_device *bdev;
 
 		spin_lock(&inode->i_lock);
 		if (inode->i_state & (I_FREEING|I_WILL_FREE|I_NEW) ||
@@ -2227,8 +2228,12 @@ void iterate_bdevs(void (*func)(struct block_device *, void *), void *arg)
 		 */
 		iput(old_inode);
 		old_inode = inode;
+		bdev = I_BDEV(inode);
 
-		func(I_BDEV(inode), arg);
+		mutex_lock(&bdev->bd_mutex);
+		if (bdev->bd_openers)
+			func(bdev, arg);
+		mutex_unlock(&bdev->bd_mutex);
 
 		spin_lock(&blockdev_superblock->s_inode_list_lock);
 	}