BUG: MAX_LOCKDEP_CHAINS too low! turning off the locking correctness validator. CPU: 1 PID: 5298 Comm: syz-executor Not tainted 6.1.148-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/30/2025 Call trace: dump_backtrace+0x1c8/0x1f4 arch/arm64/kernel/stacktrace.c:158 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165 __dump_stack+0x30/0x40 lib/dump_stack.c:88 dump_stack_lvl+0xf8/0x160 lib/dump_stack.c:106 dump_stack+0x1c/0x5c lib/dump_stack.c:113 add_chain_cache kernel/locking/lockdep.c:-1 [inline] lookup_chain_cache_add kernel/locking/lockdep.c:3772 [inline] validate_chain kernel/locking/lockdep.c:3793 [inline] __lock_acquire+0x1b40/0x6544 kernel/locking/lockdep.c:5049 lock_acquire+0x20c/0x644 kernel/locking/lockdep.c:5662 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x6c/0xb4 kernel/locking/spinlock.c:162 __stack_depot_save+0x1c4/0x4b8 lib/stackdepot.c:479 kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x64/0x80 mm/kasan/common.c:52 kasan_save_alloc_info+0x28/0x34 mm/kasan/generic.c:505 __kasan_slab_alloc+0x70/0x88 mm/kasan/common.c:328 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook+0x74/0x43c mm/slab.h:737 slab_alloc_node mm/slub.c:3398 [inline] slab_alloc mm/slub.c:3406 [inline] __kmem_cache_alloc_lru mm/slub.c:3413 [inline] kmem_cache_alloc+0x234/0x318 mm/slub.c:3422 kmem_cache_zalloc include/linux/slab.h:689 [inline] __alloc_extent_buffer+0x40/0x1d4 fs/btrfs/extent_io.c:4273 alloc_extent_buffer+0x154/0x10bc fs/btrfs/extent_io.c:4596 btrfs_find_create_tree_block+0x3c/0x50 fs/btrfs/disk-io.c:915 btrfs_init_new_buffer fs/btrfs/extent-tree.c:4918 [inline] btrfs_alloc_tree_block+0x1dc/0x1158 fs/btrfs/extent-tree.c:5037 btrfs_force_cow_block+0x3a0/0x187c fs/btrfs/ctree.c:443 btrfs_cow_block+0x2d0/0x710 fs/btrfs/ctree.c:616 commit_cowonly_roots+0x134/0x714 fs/btrfs/transaction.c:1289 btrfs_commit_transaction+0x10bc/0x29f0 fs/btrfs/transaction.c:2427 btrfs_sync_fs+0x530/0xa30 fs/btrfs/super.c:1535 sync_filesystem+0x1a0/0x218 fs/sync.c:66 generic_shutdown_super+0x70/0x324 fs/super.c:474 kill_anon_super+0x4c/0x80 fs/super.c:1128 btrfs_kill_super+0x40/0x58 fs/btrfs/super.c:2448 deactivate_locked_super+0xac/0x124 fs/super.c:332 deactivate_super+0xe8/0x108 fs/super.c:363 cleanup_mnt+0x37c/0x404 fs/namespace.c:1182 __cleanup_mnt+0x20/0x30 fs/namespace.c:1189 task_work_run+0x1ec/0x270 kernel/task_work.c:203 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] do_notify_resume+0x1f70/0x2b0c arch/arm64/kernel/signal.c:1137 prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:137 [inline] exit_to_user_mode arch/arm64/kernel/entry-common.c:142 [inline] el0_svc+0x98/0x138 arch/arm64/kernel/entry-common.c:638 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 BTRFS info (device loop6): last unmount of filesystem 395ef67a-297e-477c-816d-cd80a5b93e5d