BTRFS info (device loop5): relocating block group 6881280 flags data|metadata
BTRFS info (device loop5): relocating block group 5242880 flags data|metadata
BUG: MAX_LOCKDEP_CHAIN_HLOCKS too low!
turning off the locking correctness validator.
CPU: 0 PID: 9742 Comm: syz.5.1518 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/23/2026
dump_backtrace(regs = 0000000000000000 tsk = 0000000000000000)
Call trace:
 dump_backtrace+0x1c4/0x1f0 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+0xf4/0x15c 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:3844 [inline]
 validate_chain kernel/locking/lockdep.c:3865 [inline]
 __lock_acquire+0x2618/0x7280 kernel/locking/lockdep.c:5171
 lock_acquire+0x210/0x63c kernel/locking/lockdep.c:5790
 fs_reclaim_acquire+0xc4/0x124 mm/page_alloc.c:4766
 might_alloc include/linux/sched/mm.h:271 [inline]
 slab_pre_alloc_hook mm/slab.h:715 [inline]
 slab_alloc_node mm/slub.c:3286 [inline]
 slab_alloc mm/slub.c:3374 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3381 [inline]
 kmem_cache_alloc+0x60/0x310 mm/slub.c:3390
 kmem_cache_zalloc include/linux/slab.h:689 [inline]
 __alloc_extent_buffer+0x40/0x1e0 fs/btrfs/extent_io.c:4372
 alloc_extent_buffer+0x14c/0x10e4 fs/btrfs/extent_io.c:4695
 btrfs_find_create_tree_block+0x3c/0x50 fs/btrfs/disk-io.c:893
 btrfs_init_new_buffer fs/btrfs/extent-tree.c:4935 [inline]
 btrfs_alloc_tree_block+0x1dc/0x1178 fs/btrfs/extent-tree.c:5054
 btrfs_copy_root+0x31c/0xd30 fs/btrfs/ctree.c:221
 create_pending_snapshot+0x9ac/0x2028 fs/btrfs/transaction.c:1797
 create_pending_snapshots+0x154/0x19c fs/btrfs/transaction.c:1939
 btrfs_commit_transaction+0xff0/0x28f0 fs/btrfs/transaction.c:2413
 prepare_to_merge+0x6e8/0x11d8 fs/btrfs/relocation.c:1991
 relocate_block_group+0x7f0/0xa18 fs/btrfs/relocation.c:3819
 btrfs_relocate_block_group+0x66c/0x964 fs/btrfs/relocation.c:4159
 btrfs_relocate_chunk+0x108/0x36c fs/btrfs/volumes.c:3476
 __btrfs_balance+0x13e0/0x1b84 fs/btrfs/volumes.c:4234
 btrfs_balance+0x9f8/0xdd4 fs/btrfs/volumes.c:4610
 btrfs_ioctl_balance+0x3c8/0x600 fs/btrfs/ioctl.c:4556
 btrfs_ioctl+0x95c/0xb38 fs/btrfs/ioctl.c:5619
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl fs/ioctl.c:856 [inline]
 __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:856
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x290 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x13c/0x258 arch/arm64/kernel/syscall.c:140
 do_el0_svc+0x5c/0x134 arch/arm64/kernel/syscall.c:204
 el0_svc+0x58/0x12c arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:589
BTRFS info (device loop5): found 10 extents, stage: move data extents
BTRFS info (device loop5): found 1 extents, stage: update data pointers
BTRFS info (device loop5): balance: ended with status: 0
kcov: kcov_task_exit: t = ffff0000ccae1c00, kcov->t = ffff0000ccae1c00