From: Filipe Manana <fdmanana@suse.com> [ Upstream commit 9d123a35d7e97bb2139747b16127c9b22b6a593e ] If the caching thread fails to allocate a path, it returns without waking up any cache waiters, leaving them hang forever. Fix this by following the same approach as when we fail to start the caching thread: print an error message, disable inode caching and make the wakers fallback to non-caching mode behaviour (calling btrfs_find_free_objectid()). Fixes: 581bb050941b4f ("Btrfs: Cache free inode numbers in memory") Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> --- fs/btrfs/inode-map.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/fs/btrfs/inode-map.c b/fs/btrfs/inode-map.c index 7c4d010..c7dcb7c 100644 --- a/fs/btrfs/inode-map.c +++ b/fs/btrfs/inode-map.c @@ -41,8 +41,10 @@ static int caching_kthread(void *data) return 0; path = btrfs_alloc_path(); - if (!path) + if (!path) { + fail_caching_thread(root); return -ENOMEM; + } /* Since the commit root is read-only, we can safely skip locking. */ path->skip_locking = 1; -- 1.8.3