Increase LOCKDEP_CIRCULAR_QUEUE_BITS to avoid this warning: ------------[ cut here ]------------ lockdep bfs error:-1 WARNING: kernel/locking/lockdep.c:2059 at print_bfs_bug+0x20/0x40 kernel/locking/lockdep.c:2059, CPU#0: syz.1.3320/32211 Modules linked in: CPU: 0 UID: 0 PID: 32211 Comm: syz.1.3320 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 RIP: 0010:print_bfs_bug+0x22/0x40 kernel/locking/lockdep.c:2059 Code: 90 90 90 90 90 90 90 90 55 53 89 fb e8 77 b2 fd 02 89 c5 e8 d0 89 ff ff 85 ed 74 13 83 fb ff 74 16 48 8d 3d e0 b3 eb 0d 89 de <67> 48 0f b9 3a 5b 5d c3 cc cc cc cc cc 48 c7 c7 82 35 78 8d e8 b5 RSP: 0018:ffffc90007cb7158 EFLAGS: 00010046 RAX: 000000000000003b RBX: 00000000ffffffff RCX: f0b7a613c6ffcf00 RDX: ffffc90005861000 RSI: 00000000ffffffff RDI: ffffffff8f8c4550 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000 R10: dffffc0000000000 R11: fffff52000f96ddd R12: ffffffff960de348 R13: ffffffff931b6098 R14: ffff88805e38dc40 R15: 0000000000000049 FS: 00007f37f236e6c0(0000) GS:ffff888126170000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005566115143f8 CR3: 0000000058350000 CR4: 00000000003526f0 Call Trace: check_irq_usage kernel/locking/lockdep.c:-1 [inline] check_prev_add kernel/locking/lockdep.c:3169 [inline] check_prevs_add kernel/locking/lockdep.c:3284 [inline] validate_chain kernel/locking/lockdep.c:3908 [inline] __lock_acquire+0x2550/0x2cf0 kernel/locking/lockdep.c:5237 lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868 do_write_seqcount_begin_nested include/linux/seqlock.h:478 [inline] do_write_seqcount_begin include/linux/seqlock.h:504 [inline] psi_write_begin+0xab/0x160 kernel/sched/psi.c:183 psi_account_irqtime+0x1e2/0x6f0 kernel/sched/psi.c:1030 __schedule+0x954/0x5620 kernel/sched/core.c:7182 preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7513 irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:539 [inline] irqentry_exit+0x14f/0x760 kernel/entry/common.c:164 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:lock_acquire+0x221/0x350 kernel/locking/lockdep.c:5872 Code: ff ff ff e8 a1 4e 7d 09 f7 44 24 08 00 02 00 00 0f 84 3a ff ff ff 65 48 8b 05 3b c9 ca 10 48 3b 44 24 58 75 33 fb 48 83 c4 60 <5b> 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc 48 8d 3d 58 08 ec RSP: 0018:ffffc90007cb7728 EFLAGS: 00000286 RAX: f0b7a613c6ffcf00 RBX: 0000000000000000 RCX: 0000000000000046 RDX: 0000000000000001 RSI: ffffffff8d8673e4 RDI: ffffffff8ba759e0 RBP: ffffffff818d5335 R08: 0000000000000008 R09: ffffffff959d6b98 R10: 000000009922febe R11: 000000004a7b8065 R12: 0000000000000000 R13: ffff888060713938 R14: 0000000000000001 R15: 0000000000000246 touch_wq_lockdep_map+0xcb/0x180 kernel/workqueue.c:4029 __flush_workqueue+0x14b/0x14f0 kernel/workqueue.c:4071 drain_workqueue+0xd3/0x390 kernel/workqueue.c:4235 destroy_workqueue+0xbb/0xc60 kernel/workqueue.c:6053 btrfs_destroy_workqueue+0x45/0x230 fs/btrfs/async-thread.c:358 btrfs_stop_all_workers+0x147/0x260 fs/btrfs/disk-io.c:1747 open_ctree+0x15c0/0x4190 fs/btrfs/disk-io.c:3712 btrfs_fill_super fs/btrfs/super.c:981 [inline] btrfs_get_tree_super fs/btrfs/super.c:1944 [inline] btrfs_get_tree_subvol fs/btrfs/super.c:2087 [inline] btrfs_get_tree+0x1061/0x1910 fs/btrfs/super.c:2121 vfs_get_tree+0x92/0x2a0 fs/super.c:1754 fc_mount fs/namespace.c:1193 [inline] do_new_mount_fc fs/namespace.c:3758 [inline] do_new_mount+0x341/0xd30 fs/namespace.c:3834 do_mount fs/namespace.c:4167 [inline] __do_sys_mount fs/namespace.c:4383 [inline] __se_sys_mount+0x31d/0x420 fs/namespace.c:4360 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x15f/0x560 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f37f411e0ca Code: 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 b8 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f37f236de58 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f37f236dee0 RCX: 00007f37f411e0ca RDX: 0000200000005100 RSI: 0000200000000040 RDI: 00007f37f236dea0 RBP: 0000200000005100 R08: 00007f37f236dee0 R09: 0000000000800810 R10: 0000000000800810 R11: 0000000000000246 R12: 0000200000000040 R13: 00007f37f236dea0 R14: 000000000000510a R15: 0000200000000140 ---------------- Code disassembly (best guess): 0: 90 nop 1: 90 nop 2: 90 nop 3: 90 nop 4: 90 nop 5: 90 nop 6: 90 nop 7: 90 nop 8: 55 push %rbp 9: 53 push %rbx a: 89 fb mov %edi,%ebx c: e8 77 b2 fd 02 call 0x2fdb288 11: 89 c5 mov %eax,%ebp 13: e8 d0 89 ff ff call 0xffff89e8 18: 85 ed test %ebp,%ebp 1a: 74 13 je 0x2f 1c: 83 fb ff cmp $0xffffffff,%ebx 1f: 74 16 je 0x37 21: 48 8d 3d e0 b3 eb 0d lea 0xdebb3e0(%rip),%rdi # 0xdebb408 28: 89 de mov %ebx,%esi * 2a: 67 48 0f b9 3a ud1 (%edx),%rdi <-- trapping instruction 2f: 5b pop %rbx 30: 5d pop %rbp 31: c3 ret 32: cc int3 33: cc int3 34: cc int3 35: cc int3 36: cc int3 37: 48 c7 c7 82 35 78 8d mov $0xffffffff8d783582,%rdi 3e: e8 .byte 0xe8 3f: b5 .byte 0xb5