Increase LOCKDEP_CIRCULAR_QUEUE_BITS to avoid this warning: ------------[ cut here ]------------ lockdep bfs error:-1 WARNING: kernel/locking/lockdep.c:2103 at print_bfs_bug+0x20/0x40 kernel/locking/lockdep.c:2103, CPU#0: syz-executor958/17685 Modules linked in: CPU: 0 UID: 0 PID: 17685 Comm: syz-executor958 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026 RIP: 0010:print_bfs_bug+0x22/0x40 kernel/locking/lockdep.c:2103 Code: 90 90 90 90 90 90 90 90 55 53 89 fb e8 57 02 28 03 89 c5 e8 e0 85 ff ff 85 ed 74 13 83 fb ff 74 16 48 8d 3d d0 dc 12 0e 89 de <67> 48 0f b9 3a 5b 5d e9 c2 3e b9 09 cc 48 c7 c7 d2 51 9f 8d e8 b5 RSP: 0018:ffffc9001070f0a8 EFLAGS: 00010046 RAX: 000000000000003b RBX: 00000000ffffffff RCX: 8f72c2d048f17900 RDX: 0000000040000000 RSI: 00000000ffffffff RDI: ffffffff8fb527a0 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000 R10: dffffc0000000000 R11: fffff520020e1dc5 R12: 0000000000000017 R13: ffffffff93538e60 R14: ffffffff9643ef18 R15: ffffffff9643eff8 FS: 00007f03ee24a6c0(0000) GS:ffff888125bc7000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 0000000042370000 CR4: 00000000003526f0 Call Trace: check_irq_usage kernel/locking/lockdep.c:-1 [inline] check_prev_add kernel/locking/lockdep.c:3213 [inline] check_prevs_add kernel/locking/lockdep.c:3328 [inline] validate_chain kernel/locking/lockdep.c:3952 [inline] __lock_acquire+0x25ed/0x2de0 kernel/locking/lockdep.c:5288 lock_acquire+0x115/0x350 kernel/locking/lockdep.c:5942 seqcount_lockdep_reader_access+0x55/0x100 include/linux/seqlock.h:73 ktime_get+0x45/0x220 kernel/time/timekeeping.c:1002 clockevents_program_event+0x290/0x630 kernel/time/clockevents.c:363 hrtimer_rearm kernel/time/hrtimer.c:2176 [inline] __hrtimer_rearm_deferred+0x37e/0x4d0 kernel/time/hrtimer.c:2196 hrtimer_rearm_deferred_tif include/linux/hrtimer_rearm.h:58 [inline] hrtimer_rearm_deferred include/linux/hrtimer_rearm.h:67 [inline] irqentry_exit_to_kernel_mode_after_preempt include/linux/irq-entry-common.h:505 [inline] irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:542 [inline] irqentry_exit+0x8d3/0x910 kernel/entry/common.c:167 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674 RIP: 0010:finish_task_switch+0x413/0xc60 kernel/sched/core.c:5384 Code: 04 00 00 41 c7 84 24 20 0e 00 00 00 00 00 00 0f 1f 44 00 00 49 83 c4 48 4c 89 e7 e8 27 73 c5 09 e8 c2 2e 39 00 fb 4c 8b 65 c8 <49> 8d bc 24 f8 16 00 00 48 89 f8 48 c1 e8 03 42 0f b6 04 30 84 c0 RSP: 0018:ffffc9001070f500 EFLAGS: 00000202 RAX: 00000000000007d9 RBX: ffff8880b863d0e0 RCX: 8000000000000001 RDX: 0000000000000006 RSI: ffffffff8d86bf07 RDI: ffffffff8bcc4580 RBP: ffffc9001070f550 R08: ffffffff8fb2197f R09: 1ffffffff1f6432f R10: dffffc0000000000 R11: fffffbfff1f64330 R12: ffff88801ffc5dc0 R13: ffff8880b863d0a8 R14: dffffc0000000000 R15: 1ffff110170c7a1c context_switch kernel/sched/core.c:5536 [inline] __schedule+0x16e1/0x5700 kernel/sched/core.c:7284 preempt_schedule_irq+0x4b/0x90 kernel/sched/core.c:7606 irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:539 [inline] irqentry_exit+0x14f/0x910 kernel/entry/common.c:167 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674 RIP: 0010:lock_acquire+0x232/0x350 kernel/locking/lockdep.c:5947 Code: ff ff ff e8 20 c8 b5 09 f7 44 24 10 00 02 00 00 0f 84 38 ff ff ff 65 48 8b 05 22 a3 03 11 48 3b 44 24 50 75 33 fb 48 83 c4 58 <5b> 41 5c 41 5d 41 5e 41 5f 5d e9 7f 9c b9 09 cc 48 8d 3d 87 34 13 RSP: 0018:ffffc9001070f888 EFLAGS: 00000286 RAX: 8f72c2d048f17900 RBX: 0000000000000001 RCX: 0000000000000046 RDX: ffff88801ffc6a00 RSI: ffffffff8dadf042 RDI: ffffffff8bcc4580 RBP: ffff88801ffc5dc0 R08: 0000000000000008 R09: ffffffff95cd0ce8 R10: 00000000631be513 R11: 00000000346ec0f7 R12: ffff88803f9fd138 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000246 touch_wq_lockdep_map+0xcb/0x180 kernel/workqueue.c:4111 __flush_workqueue+0x148/0x1470 kernel/workqueue.c:4153 drain_workqueue+0xce/0x380 kernel/workqueue.c:4317 destroy_workqueue+0xbb/0xc60 kernel/workqueue.c:6155 xfs_destroy_mount_workqueues+0xad/0x100 fs/xfs/xfs_super.c:703 xfs_fs_fill_super+0x679/0x15a0 fs/xfs/xfs_super.c:2019 get_tree_bdev_flags+0x430/0x4f0 fs/super.c:1873 vfs_get_tree+0x92/0x2a0 fs/super.c:1933 fc_mount fs/namespace.c:1198 [inline] do_new_mount_fc fs/namespace.c:3772 [inline] do_new_mount+0x319/0xdc0 fs/namespace.c:3848 do_mount fs/namespace.c:4181 [inline] __do_sys_mount fs/namespace.c:4397 [inline] __se_sys_mount+0x31d/0x420 fs/namespace.c:4374 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f03ee27f679 Code: c0 79 93 eb d5 48 8d 7c 1d 00 eb 99 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 d0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f03ee24a128 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f03ee325b28 RCX: 00007f03ee27f679 RDX: 0000200000000000 RSI: 00002000000001c0 RDI: 0000200000000080 RBP: 00007f03ee325b20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000001a0c099 R11: 0000000000000246 R12: 00007f03ee325b2c R13: 0000000000000006 R14: 00007fffea9b4890 R15: 00007fffea9b4978 ---------------- 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 57 02 28 03 call 0x3280268 11: 89 c5 mov %eax,%ebp 13: e8 e0 85 ff ff call 0xffff85f8 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 d0 dc 12 0e lea 0xe12dcd0(%rip),%rdi # 0xe12dcf8 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: e9 c2 3e b9 09 jmp 0x9b93ef8 36: cc int3 37: 48 c7 c7 d2 51 9f 8d mov $0xffffffff8d9f51d2,%rdi 3e: e8 .byte 0xe8 3f: b5 .byte 0xb5