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We are in the chunk allocation thread. The newer chunk allocation happens from the devices in the fs_device->alloc_list protected by the chunk_mutex. btrfs_create_chunk() lockdep_assert_held(&info->chunk_mutex); gather_device_info list_for_each_entry(device, &fs_devices->alloc_list, dev_alloc_list) { Also, a device reappeared after the mount won't join the alloc_list yet and, it will be in the dev_list, which we don't want to consider in the context of the chunk alloc. Thanks, Anand