diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index d48274451452..7a30dd8ffdb5 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -710,17 +710,28 @@ static struct btrfs_fs_devices *find_fsid_changed( /* * Handles the case where scanned device is part of an fs that had * multiple successful changes of FSID but curently device didn't - * observe it. Meaning our fsid will be different than theirs. + * observe it. Meaning our fsid will be different than theirs. We need + * to handle two subcases : + * 1 - The fs still continues to have different METADATA/FSID uuids. + * 2 - The fs is switched back to its original FSID (METADATA/FSID + * are equal). */ list_for_each_entry(fs_devices, &fs_uuids, fs_list) { + /* Changed UUIDs */ if (memcmp(fs_devices->metadata_uuid, fs_devices->fsid, BTRFS_FSID_SIZE) != 0 && memcmp(fs_devices->metadata_uuid, disk_super->metadata_uuid, BTRFS_FSID_SIZE) == 0 && memcmp(fs_devices->fsid, disk_super->fsid, - BTRFS_FSID_SIZE) != 0) { + BTRFS_FSID_SIZE) != 0) + return fs_devices; + + /* Unchanged UUIDs */ + if (memcmp(fs_devices->metadata_uuid, fs_devices->fsid, + BTRFS_FSID_SIZE) == 0 && + memcmp(fs_devices->fsid, disk_super->metadata_uuid, + BTRFS_FSID_SIZE) == 0) return fs_devices; - } } return NULL;