================================ WARNING: inconsistent lock state syzkaller #0 Tainted: G L -------------------------------- inconsistent {HARDIRQ-ON-W} -> {IN-HARDIRQ-W} usage. dhcpcd/5482 [HC1[1]:SC0[0]:HE0:SE1] takes: ffff888032187868 (&dev->spinlock){?...}-{3:3}, at: spin_lock include/linux/spinlock.h:341 [inline] ffff888032187868 (&dev->spinlock){?...}-{3:3}, at: das16m1_interrupt+0x68/0x120 drivers/comedi/drivers/das16m1.c:460 {HARDIRQ-ON-W} state was registered at: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x1cf/0x380 kernel/locking/lockdep.c:5825 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:150 [inline] _raw_spin_lock_bh+0x33/0x40 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:347 [inline] waveform_ao_cancel+0x96/0x150 drivers/comedi/drivers/comedi_test.c:628 do_cancel+0xf4/0x180 drivers/comedi/comedi_fops.c:818 comedi_close+0x2f6/0x470 drivers/comedi/comedi_fops.c:3036 __fput+0x3ff/0xb40 fs/file_table.c:469 task_work_run+0x150/0x240 kernel/task_work.c:233 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] __exit_to_user_mode_loop kernel/entry/common.c:67 [inline] exit_to_user_mode_loop+0x100/0x4a0 kernel/entry/common.c:98 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline] do_syscall_64+0x67c/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f irq event stamp: 235036 hardirqs last enabled at (235035): [] seqcount_lockdep_reader_access include/linux/seqlock.h:75 [inline] hardirqs last enabled at (235035): [] read_seqbegin include/linux/seqlock.h:838 [inline] hardirqs last enabled at (235035): [] zone_span_seqbegin include/linux/memory_hotplug.h:87 [inline] hardirqs last enabled at (235035): [] page_outside_zone_boundaries mm/page_alloc.c:612 [inline] hardirqs last enabled at (235035): [] bad_range+0x261/0x400 mm/page_alloc.c:631 hardirqs last disabled at (235036): [] common_interrupt+0x19/0xe0 arch/x86/kernel/irq.c:326 softirqs last enabled at (235032): [] local_bh_disable include/linux/bottom_half.h:20 [inline] softirqs last enabled at (235032): [] __alloc_skb+0x5b7/0x710 net/core/skbuff.c:695 softirqs last disabled at (235030): [] local_bh_disable include/linux/bottom_half.h:20 [inline] softirqs last disabled at (235030): [] __alloc_skb+0x5b7/0x710 net/core/skbuff.c:695 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&dev->spinlock); lock(&dev->spinlock); *** DEADLOCK *** 3 locks held by dhcpcd/5482: #0: ffff888020ba86f0 (nlk_cb_mutex-ROUTE){+.+.}-{4:4}, at: __netlink_dump_start+0x150/0x990 net/netlink/af_netlink.c:2404 #1: ffffffff8e7e7920 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #1: ffffffff8e7e7920 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #1: ffffffff8e7e7920 (rcu_read_lock){....}-{1:3}, at: inet_dump_fib+0x12f/0x990 net/ipv4/fib_frontend.c:1033 #2: ffffffff8e7e7920 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #2: ffffffff8e7e7920 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #2: ffffffff8e7e7920 (rcu_read_lock){....}-{1:3}, at: fib_dump_info_fnhe+0x24b/0x12e0 net/ipv4/route.c:3145 stack backtrace: CPU: 0 UID: 101 PID: 5482 Comm: dhcpcd Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 print_usage_bug.part.0+0x257/0x340 kernel/locking/lockdep.c:4042 print_usage_bug kernel/locking/lockdep.c:4010 [inline] valid_state kernel/locking/lockdep.c:4056 [inline] mark_lock_irq kernel/locking/lockdep.c:4267 [inline] mark_lock+0x74a/0xa20 kernel/locking/lockdep.c:4753 mark_usage kernel/locking/lockdep.c:4639 [inline] __lock_acquire+0x10ff/0x2630 kernel/locking/lockdep.c:5191 lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x1cf/0x380 kernel/locking/lockdep.c:5825 __raw_spin_lock include/linux/spinlock_api_smp.h:158 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:341 [inline] das16m1_interrupt+0x68/0x120 drivers/comedi/drivers/das16m1.c:460 __handle_irq_event_percpu+0x232/0x8e0 kernel/irq/handle.c:209 handle_irq_event_percpu kernel/irq/handle.c:246 [inline] handle_irq_event+0xab/0x1e0 kernel/irq/handle.c:263 handle_edge_irq+0x375/0x970 kernel/irq/chip.c:855 generic_handle_irq_desc include/linux/irqdesc.h:186 [inline] handle_irq arch/x86/kernel/irq.c:262 [inline] call_irq_handler arch/x86/kernel/irq.c:318 [inline] __common_interrupt+0xd8/0x2f0 arch/x86/kernel/irq.c:333 common_interrupt+0xb9/0xe0 arch/x86/kernel/irq.c:326 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:688 RIP: 0010:debug_lockdep_rcu_enabled+0x0/0x40 kernel/rcu/update.c:319 Code: 00 00 8b 44 24 04 eb b2 89 44 24 04 e8 a9 fa ff ff 8b 44 24 04 eb aa 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 8b 05 82 5b 4a 05 85 c0 74 20 8b 05 60 8e 4a 05 85 c0 RSP: 0018:ffffc900030f7118 EFLAGS: 00000286 RAX: 0000000000000000 RBX: ffff88801eb23c80 RCX: 0000000000000002 RDX: 0000000000000000 RSI: ffffffff8de5e4ed RDI: ffffffff8c1b1a20 RBP: 0000000000000000 R08: 00000000992858fd R09: 0000000000000007 R10: 0000000000000200 R11: 0000000000000000 R12: ffff88801eb23c00 R13: 0000000000000000 R14: ffffc900030f72f8 R15: dffffc0000000000 rcu_read_lock include/linux/rcupdate.h:851 [inline] fib_dump_info_fnhe+0x261/0x12e0 net/ipv4/route.c:3145 fn_trie_dump_leaf net/ipv4/fib_trie.c:2309 [inline] fib_table_dump+0x658/0xd40 net/ipv4/fib_trie.c:2349 inet_dump_fib+0x394/0x990 net/ipv4/fib_frontend.c:1075 rtnl_dumpit+0x97/0x1f0 net/core/rtnetlink.c:6849 netlink_dump+0x539/0xd30 net/netlink/af_netlink.c:2325 __netlink_dump_start+0x6d6/0x990 net/netlink/af_netlink.c:2440 netlink_dump_start include/linux/netlink.h:341 [inline] rtnetlink_dump_start net/core/rtnetlink.c:6878 [inline] rtnetlink_rcv_msg+0xb3e/0xe90 net/core/rtnetlink.c:6945 netlink_rcv_skb+0x159/0x420 net/netlink/af_netlink.c:2550 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x5aa/0x870 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x8b0/0xda0 net/netlink/af_netlink.c:1894 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg net/socket.c:742 [inline] ____sys_sendmsg+0x9e1/0xb70 net/socket.c:2592 ___sys_sendmsg+0x190/0x1e0 net/socket.c:2646 __sys_sendmsg+0x170/0x220 net/socket.c:2678 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f7c931c6407 Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff RSP: 002b:00007ffe900520f0 EFLAGS: 00000202 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f7c9313c780 RCX: 00007f7c931c6407 RDX: 0000000000000000 RSI: 00007ffe90052170 RDI: 000000000000000c RBP: 00007ffe90056390 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 000055963c91ac60 R13: 000000000000000c R14: 00007ffe90056350 R15: 00007ffe90056390 comedi comedi3: fifo overflow ---------------- Code disassembly (best guess): 0: 00 00 add %al,(%rax) 2: 8b 44 24 04 mov 0x4(%rsp),%eax 6: eb b2 jmp 0xffffffba 8: 89 44 24 04 mov %eax,0x4(%rsp) c: e8 a9 fa ff ff call 0xfffffaba 11: 8b 44 24 04 mov 0x4(%rsp),%eax 15: eb aa jmp 0xffffffc1 17: 0f 1f 00 nopl (%rax) 1a: 90 nop 1b: 90 nop 1c: 90 nop 1d: 90 nop 1e: 90 nop 1f: 90 nop 20: 90 nop 21: 90 nop 22: 90 nop 23: 90 nop 24: 90 nop 25: 90 nop 26: 90 nop 27: 90 nop 28: 90 nop 29: 90 nop * 2a: f3 0f 1e fa endbr64 <-- trapping instruction 2e: 8b 05 82 5b 4a 05 mov 0x54a5b82(%rip),%eax # 0x54a5bb6 34: 85 c0 test %eax,%eax 36: 74 20 je 0x58 38: 8b 05 60 8e 4a 05 mov 0x54a8e60(%rip),%eax # 0x54a8e9e 3e: 85 c0 test %eax,%eax