Commit 213e64da authored by Ilya Dryomov's avatar Ilya Dryomov
Browse files

Btrfs: fix infinite loop in btrfs_shrink_device() 



If relocate of block group 0 fails with ENOSPC we end up infinitely
looping because key.offset -= 1 statement in that case brings us back to
where we started.

Signed-off-by: default avatarIlya Dryomov <idryomov@gmail.com>
parent 5eb56d25

fs/btrfs/volumes.c

+2 −3
Original line number Diff line number Diff line
@@ -2987,7 +2987,7 @@ int btrfs_shrink_device(struct btrfs_device *device, u64 new_size) 
	key.offset = (u64)-1;

	key.type = BTRFS_DEV_EXTENT_KEY;



	while (1) {

	do {

		ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);

		if (ret < 0)

			goto done;
@@ -3029,8 +3029,7 @@ int btrfs_shrink_device(struct btrfs_device *device, u64 new_size) 
			goto done;

		if (ret == -ENOSPC)

			failed++;

		key.offset -= 1;

	}

	} while (key.offset-- > 0);



	if (failed && !retried) {

		failed = 0;