diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 39d8e39..0b6567f 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -915,8 +915,10 @@
 				error = -ENOMEM;
 				goto out;
 			}
+			mutex_lock(&uuid_mutex);
 			error = btrfs_scan_one_device(device_name,
 					flags, holder, fs_devices);
+			mutex_unlock(&uuid_mutex);
 			kfree(device_name);
 			if (error)
 				goto out;
@@ -1537,7 +1539,9 @@
 			return ERR_PTR(error);
 	}
 
+	mutex_lock(&uuid_mutex);
 	error = btrfs_scan_one_device(device_name, mode, fs_type, &fs_devices);
+	mutex_unlock(&uuid_mutex);
 	if (error)
 		goto error_sec_opts;
 
@@ -2232,15 +2236,21 @@
 
 	switch (cmd) {
 	case BTRFS_IOC_SCAN_DEV:
+		mutex_lock(&uuid_mutex);
 		ret = btrfs_scan_one_device(vol->name, FMODE_READ,
 					    &btrfs_root_fs_type, &fs_devices);
+		mutex_unlock(&uuid_mutex);
 		break;
 	case BTRFS_IOC_DEVICES_READY:
+		mutex_lock(&uuid_mutex);
 		ret = btrfs_scan_one_device(vol->name, FMODE_READ,
 					    &btrfs_root_fs_type, &fs_devices);
-		if (ret)
+		if (ret) {
+			mutex_unlock(&uuid_mutex);
 			break;
+		}
 		ret = !(fs_devices->num_devices == fs_devices->total_devices);
+		mutex_unlock(&uuid_mutex);
 		break;
 	case BTRFS_IOC_GET_SUPPORTED_FEATURES:
 		ret = btrfs_ioctl_get_supported_features((void __user*)arg);
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 6a8f1e2..df5dd6f 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -1224,6 +1224,8 @@
 	int ret = 0;
 	u64 bytenr;
 
+	lockdep_assert_held(&uuid_mutex);
+
 	/*
 	 * we would like to check all the supers, but that would make
 	 * a btrfs mount succeed after a mkfs from a different FS.
@@ -1242,7 +1244,6 @@
 		goto error_bdev_put;
 	}
 
-	mutex_lock(&uuid_mutex);
 	device = device_list_add(path, disk_super, &new_device_added);
 	if (IS_ERR(device)) {
 		ret = PTR_ERR(device);
@@ -1251,7 +1252,6 @@
 		if (new_device_added)
 			btrfs_free_stale_devices(path, device);
 	}
-	mutex_unlock(&uuid_mutex);
 
 	btrfs_release_disk_super(page);