================================ WARNING: inconsistent lock state syzkaller #0 Tainted: G L -------------------------------- inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage. ksoftirqd/0/15 [HC0[0]:SC1[1]:HE1:SE0] takes: ffff888079b34260 (sk_lock-AF_X25){+.?.}-{0:0}, at: lock_sock include/net/sock.h:1715 [inline] ffff888079b34260 (sk_lock-AF_X25){+.?.}-{0:0}, at: x25_kill_by_neigh+0x10d/0x250 net/x25/af_x25.c:1775 {SOFTIRQ-ON-W} state was registered at: lock_acquire+0x115/0x350 kernel/locking/lockdep.c:5942 lock_sock_nested+0x41/0x100 net/core/sock.c:3879 lock_sock include/net/sock.h:1715 [inline] x25_release+0xa0/0x3d0 net/x25/af_x25.c:629 __sock_release+0xa0/0x1f0 net/socket.c:735 sock_close+0x1c/0x30 net/socket.c:1529 __fput+0x408/0xa40 fs/file_table.c:513 fput_close_sync+0x11f/0x240 fs/file_table.c:619 filp_close_sync+0x6e/0xa0 fs/open.c:1897 __range_close fs/file.c:919 [inline] __do_sys_close_range fs/file.c:1003 [inline] __se_sys_close_range+0xa77/0xef0 fs/file.c:954 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 irq event stamp: 966580 hardirqs last enabled at (966580): [] __local_bh_enable_ip+0xd6/0x140 kernel/softirq.c:478 hardirqs last disabled at (966579): [] __local_bh_enable_ip+0x72/0x140 kernel/softirq.c:455 softirqs last enabled at (966494): [] run_ksoftirqd+0x36/0x60 kernel/softirq.c:1099 softirqs last disabled at (966507): [] run_ksoftirqd+0x36/0x60 kernel/softirq.c:1099 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(sk_lock-AF_X25); lock(sk_lock-AF_X25); *** DEADLOCK *** locks held by ksoftirqd/0/15: 1, last CPU#0: #0: ffffffff8fd5a2a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #0: ffffffff8fd5a2a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8fd5a2a0 (rcu_read_lock){....}-{1:3}, at: netif_receive_skb_core+0x33/0x2b0 net/core/dev.c:6359 stack backtrace: CPU: 0 UID: 0 PID: 15 Comm: ksoftirqd/0 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_usage_bug+0x28c/0x2e0 kernel/locking/lockdep.c:4086 valid_state+0xbe/0xf0 kernel/locking/lockdep.c:4100 mark_lock_irq+0x36/0x380 kernel/locking/lockdep.c:4311 mark_lock+0x117/0x190 kernel/locking/lockdep.c:4797 mark_usage kernel/locking/lockdep.c:-1 [inline] __lock_acquire+0x71e/0x2de0 kernel/locking/lockdep.c:5242 lock_acquire+0x115/0x350 kernel/locking/lockdep.c:5942 lock_sock_nested+0x41/0x100 net/core/sock.c:3879 lock_sock include/net/sock.h:1715 [inline] x25_kill_by_neigh+0x10d/0x250 net/x25/af_x25.c:1775 x25_lapb_receive_frame+0x1b0/0xfb0 net/x25/x25_dev.c:138 __netif_receive_skb_one_core net/core/dev.c:6335 [inline] netif_receive_skb_core+0x2a6/0x2b0 net/core/dev.c:6360 lapbeth_napi_poll+0x42/0x90 drivers/net/wan/lapbether.c:100 __napi_poll+0xaa/0x330 net/core/dev.c:7868 napi_poll net/core/dev.c:7931 [inline] net_rx_action+0x61d/0xf50 net/core/dev.c:8088 handle_softirqs+0x223/0x840 kernel/softirq.c:645 run_ksoftirqd+0x36/0x60 kernel/softirq.c:1099 smpboot_thread_fn+0x5f8/0xb30 kernel/smpboot.c:162 kthread+0x38b/0x480 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 BUG: sleeping function called from invalid context at net/core/sock.c:3881 in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 15, name: ksoftirqd/0 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:486 [inline] [] handle_softirqs+0xab/0x840 kernel/softirq.c:621 CPU: 0 UID: 0 PID: 15 Comm: ksoftirqd/0 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 __might_resched+0x36a/0x4c0 kernel/sched/core.c:9200 lock_sock_nested+0x56/0x100 net/core/sock.c:3881 lock_sock include/net/sock.h:1715 [inline] x25_kill_by_neigh+0x10d/0x250 net/x25/af_x25.c:1775 x25_lapb_receive_frame+0x1b0/0xfb0 net/x25/x25_dev.c:138 __netif_receive_skb_one_core net/core/dev.c:6335 [inline] netif_receive_skb_core+0x2a6/0x2b0 net/core/dev.c:6360 lapbeth_napi_poll+0x42/0x90 drivers/net/wan/lapbether.c:100 __napi_poll+0xaa/0x330 net/core/dev.c:7868 napi_poll net/core/dev.c:7931 [inline] net_rx_action+0x61d/0xf50 net/core/dev.c:8088 handle_softirqs+0x223/0x840 kernel/softirq.c:645 run_ksoftirqd+0x36/0x60 kernel/softirq.c:1099 smpboot_thread_fn+0x5f8/0xb30 kernel/smpboot.c:162 kthread+0x38b/0x480 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245