Got this while building bolt in a podman container. I've got reproduce steps and test files here https://bugzilla.redhat.com/show_bug.cgi?id=1948054
[ 3229.119497] overlayfs: upper fs does not support xattr, falling back to index=off and metacopy=off. [ 3229.155339] overlayfs: upper fs does not support xattr, falling back to index=off and metacopy=off. [ 3238.380647] BUG: MAX_LOCKDEP_CHAIN_HLOCKS too low! [ 3238.380654] turning off the locking correctness validator. [ 3238.380656] Please attach the output of /proc/lock_stat to the bug report [ 3238.380657] CPU: 4 PID: 9115 Comm: kworker/u16:20 Not tainted 5.12.0-0.rc6.184.fc35.x86_64+debug #1 [ 3238.380660] Hardware name: Apple Inc. MacBookPro8,2/Mac-94245A3940C91C80, BIOS MBP81.88Z.0050.B00.1804101331 04/10/18 [ 3238.380663] Workqueue: btrfs-delalloc btrfs_work_helper [ 3238.380670] Call Trace: [ 3238.380674] dump_stack+0x7f/0xa1 [ 3238.380680] __lock_acquire.cold+0x1a9/0x2bf [ 3238.380686] ? __lock_acquire+0x3ac/0x1e10 [ 3238.380691] lock_acquire+0xc4/0x3a0 [ 3238.380695] ? percpu_counter_add_batch+0x45/0x60 [ 3238.380699] ? lock_acquire+0xc4/0x3a0 [ 3238.380702] ? lock_is_held_type+0xa7/0x120 [ 3238.380706] ? __set_page_dirty_nobuffers+0x6b/0x1e0 [ 3238.380711] _raw_spin_lock_irqsave+0x4d/0x90 [ 3238.380715] ? percpu_counter_add_batch+0x45/0x60 [ 3238.380718] percpu_counter_add_batch+0x45/0x60 [ 3238.380721] account_page_dirtied+0x102/0x320 [ 3238.380724] __set_page_dirty_nobuffers+0xa2/0x1e0 [ 3238.380727] set_extent_buffer_dirty+0x63/0x80 [ 3238.380732] btrfs_mark_buffer_dirty+0x60/0x80 [ 3238.380737] copy_for_split+0x29e/0x360 [ 3238.380741] split_leaf+0x1c2/0x5e0 [ 3238.380746] btrfs_search_slot+0x99a/0x9f0 [ 3238.380751] btrfs_insert_empty_items+0x58/0xa0 [ 3238.380754] cow_file_range_inline.constprop.0+0x1cf/0x760 [ 3238.380758] ? __local_bh_enable_ip+0x82/0xd0 [ 3238.380762] ? zstd_put_workspace+0x82/0x160 [ 3238.380765] ? __local_bh_enable_ip+0x82/0xd0 [ 3238.380769] compress_file_range+0x471/0x830 [ 3238.380774] async_cow_start+0x12/0x30 [ 3238.380777] ? submit_compressed_extents+0x410/0x410 [ 3238.380779] btrfs_work_helper+0x105/0x400 [ 3238.380782] ? lock_is_held_type+0xa7/0x120 [ 3238.380786] process_one_work+0x2b0/0x5e0 [ 3238.380791] worker_thread+0x55/0x3c0 [ 3238.380793] ? process_one_work+0x5e0/0x5e0 [ 3238.380796] kthread+0x13a/0x150 [ 3238.380799] ? __kthread_bind_mask+0x60/0x60 [ 3238.380801] ret_from_fork+0x1f/0x30 The /proc/lock_stat is in the downstream bug as an attachment. There's possibly three things going on here, the bogus overlayfs warning, the lockdep bug, and the call trace with btrfs bits in it. No idea if they are related.
