================================ WARNING: inconsistent lock state syzkaller #0 Not tainted -------------------------------- inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage. ksoftirqd/1/21 [HC0[0]:SC1[1]:HE1:SE0] takes: ffff888020752130 (sk_lock-AF_X25){+.?.}-{0:0}, at: lock_sock include/net/sock.h:1805 [inline] ffff888020752130 (sk_lock-AF_X25){+.?.}-{0:0}, at: x25_kill_by_neigh+0x83/0x120 net/x25/af_x25.c:1781 {SOFTIRQ-ON-W} state was registered at: lock_acquire+0x1bb/0x4a0 kernel/locking/lockdep.c:5676 lock_sock_nested+0x44/0x100 net/core/sock.c:3505 lock_sock include/net/sock.h:1805 [inline] x25_release+0x9c/0x380 net/x25/af_x25.c:636 __sock_release net/socket.c:654 [inline] sock_close+0xbf/0x210 net/socket.c:1400 __fput+0x20a/0x8b0 fs/file_table.c:320 task_work_run+0x1d0/0x260 kernel/task_work.c:203 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x68/0xd2 irq event stamp: 2274272 hardirqs last enabled at (2274272): [] __local_bh_enable_ip+0x136/0x1c0 kernel/softirq.c:426 hardirqs last disabled at (2274271): [] __local_bh_enable_ip+0xd7/0x1c0 kernel/softirq.c:403 softirqs last enabled at (2273570): [] run_ksoftirqd+0xa4/0x100 kernel/softirq.c:968 softirqs last disabled at (2273575): [] run_ksoftirqd+0xa4/0x100 kernel/softirq.c:968 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(sk_lock-AF_X25); lock(sk_lock-AF_X25); *** DEADLOCK *** 1 lock held by ksoftirqd/1/21: #0: ffffffff8cb2db60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #0: ffffffff8cb2db60 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #0: ffffffff8cb2db60 (rcu_read_lock){....}-{1:2}, at: netif_receive_skb_core+0x30/0x230 net/core/dev.c:5643 stack backtrace: CPU: 1 PID: 21 Comm: ksoftirqd/1 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Call Trace: dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106 valid_state+0x13b/0x1d0 kernel/locking/lockdep.c:3974 mark_lock_irq+0xa9/0x900 kernel/locking/lockdep.c:4177 mark_lock+0x208/0x320 kernel/locking/lockdep.c:4633 mark_usage kernel/locking/lockdep.c:-1 [inline] __lock_acquire+0xce0/0x7c40 kernel/locking/lockdep.c:5017 lock_acquire+0x1bb/0x4a0 kernel/locking/lockdep.c:5676 lock_sock_nested+0x44/0x100 net/core/sock.c:3505 lock_sock include/net/sock.h:1805 [inline] x25_kill_by_neigh+0x83/0x120 net/x25/af_x25.c:1781 x25_lapb_receive_frame+0x1a3/0xf20 net/x25/x25_dev.c:138 __netif_receive_skb_one_core net/core/dev.c:5619 [inline] netif_receive_skb_core+0x166/0x230 net/core/dev.c:5644 lapbeth_napi_poll+0x3e/0x80 drivers/net/wan/lapbether.c:99 __napi_poll+0xbb/0x460 net/core/dev.c:6628 napi_poll net/core/dev.c:6695 [inline] net_rx_action+0x622/0xbc0 net/core/dev.c:6809 handle_softirqs+0x291/0x910 kernel/softirq.c:596 run_ksoftirqd+0xa4/0x100 kernel/softirq.c:968 smpboot_thread_fn+0x667/0xa30 kernel/smpboot.c:164 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 BUG: sleeping function called from invalid context at net/core/sock.c:3507 in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 21, name: ksoftirqd/1 preempt_count: 100, expected: 0 RCU nest depth: 1, expected: 0 INFO: lockdep is turned off. Preemption disabled at: [] softirq_handle_begin kernel/softirq.c:434 [inline] [] handle_softirqs+0xfd/0x910 kernel/softirq.c:572 CPU: 1 PID: 21 Comm: ksoftirqd/1 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Call Trace: dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106 __might_resched+0x489/0x5f0 kernel/sched/core.c:9970 lock_sock_nested+0x59/0x100 net/core/sock.c:3507 lock_sock include/net/sock.h:1805 [inline] x25_kill_by_neigh+0x83/0x120 net/x25/af_x25.c:1781 x25_lapb_receive_frame+0x1a3/0xf20 net/x25/x25_dev.c:138 __netif_receive_skb_one_core net/core/dev.c:5619 [inline] netif_receive_skb_core+0x166/0x230 net/core/dev.c:5644 lapbeth_napi_poll+0x3e/0x80 drivers/net/wan/lapbether.c:99 __napi_poll+0xbb/0x460 net/core/dev.c:6628 napi_poll net/core/dev.c:6695 [inline] net_rx_action+0x622/0xbc0 net/core/dev.c:6809 handle_softirqs+0x291/0x910 kernel/softirq.c:596 run_ksoftirqd+0xa4/0x100 kernel/softirq.c:968 smpboot_thread_fn+0x667/0xa30 kernel/smpboot.c:164 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295