syzbot

watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [syz.4.511:6617]
Modules linked in:
irq event stamp: 1253579
hardirqs last  enabled at (1253578): [<ffff8000083b9464>] seqcount_lockdep_reader_access include/linux/seqlock.h:104 [inline]
hardirqs last  enabled at (1253578): [<ffff8000083b9464>] timekeeping_get_delta kernel/time/timekeeping.c:254 [inline]
hardirqs last  enabled at (1253578): [<ffff8000083b9464>] timekeeping_get_ns+0x124/0x3b8 kernel/time/timekeeping.c:388
hardirqs last disabled at (1253579): [<ffff800011957760>] __el1_irq arch/arm64/kernel/entry-common.c:468 [inline]
hardirqs last disabled at (1253579): [<ffff800011957760>] el1_interrupt+0x24/0x54 arch/arm64/kernel/entry-common.c:486
softirqs last  enabled at (1358): [<ffff8000113900f4>] spin_unlock_bh include/linux/spinlock.h:396 [inline]
softirqs last  enabled at (1358): [<ffff8000113900f4>] tipc_disc_reset+0x1dc/0x2f8 net/tipc/discover.c:417
softirqs last disabled at (1360): [<ffff80000fd3efc4>] local_bh_disable+0x10/0x34 include/linux/bottom_half.h:19
CPU: 0 PID: 6617 Comm: syz.4.511 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/30/2025
pstate: 62400005 (nZCv daif +PAN -UAO +TCO -DIT -SSBS BTYPE=--)
pc : cake_heapify+0x4dc/0x530 net/sched/sch_cake.c:1510
lr : cake_heapify+0x4c4/0x530 net/sched/sch_cake.c:1503
sp : ffff800021b86a50
x29: ffff800021b86a60 x28: dfff800000000000 x27: 00000000000198d0
x26: 000000000003c166 x25: ffff0000db6fc2d8 x24: 0000000000000000
x23: ffff0000db6f82d0 x22: ffff0000db6fc2d8 x21: ffff0000db6f82c0
x20: 0000000000000500 x19: 0000000000000991 x18: ffff800011abbcc0
x17: ffff8000181f9000 x16: ffff8000082d22e0 x15: ffff800017cd9fc0
x14: ffff0000dab6ddd8 x13: 1ffff00002a180b1 x12: 0000000000080000
x11: 000000000007ffff x10: ffff80002aa72000 x9 : ffff80000ffc9c34
x8 : 0000000000080000 x7 : ffff8000083b9870 x6 : 0000000000000000
x5 : 0000000000000080 x4 : 0000000000000001 x3 : 0000000000000000
x2 : 0000000000000002 x1 : 0000000000000991 x0 : 0000000000000991
Call trace:
 cake_heapify+0x4dc/0x530 net/sched/sch_cake.c:1510
 cake_drop net/sched/sch_cake.c:1575 [inline]
 cake_enqueue+0x32dc/0x6670 net/sched/sch_cake.c:1948
 qdisc_enqueue include/net/sch_generic.h:816 [inline]
 netem_dequeue+0xa74/0x107c net/sched/sch_netem.c:737
 dequeue_skb net/sched/sch_generic.c:292 [inline]
 qdisc_restart net/sched/sch_generic.c:397 [inline]
 __qdisc_run+0x1c4/0x1368 net/sched/sch_generic.c:415
 __dev_xmit_skb net/core/dev.c:3970 [inline]
 __dev_queue_xmit+0xc18/0x309c net/core/dev.c:4312
 dev_queue_xmit include/linux/netdevice.h:3051 [inline]
 tipc_l2_send_msg+0x29c/0x35c net/tipc/bearer.c:518
 tipc_bearer_xmit_skb+0x244/0x384 net/tipc/bearer.c:577
 tipc_disc_reset+0x200/0x2f8 net/tipc/discover.c:419
 tipc_reset_bearer+0x5c/0x84 net/tipc/bearer.c:387
 tipc_l2_device_event+0x498/0x778 net/tipc/bearer.c:-1
 notifier_call_chain kernel/notifier.c:87 [inline]
 raw_notifier_call_chain+0xd4/0x164 kernel/notifier.c:455
 call_netdevice_notifiers_info net/core/dev.c:2001 [inline]
 call_netdevice_notifiers_mtu+0x118/0x19c net/core/dev.c:2076
 dev_set_mtu_ext+0x350/0x514 net/core/dev.c:8780
 dev_set_mtu+0x50/0xe8 net/core/dev.c:8801
 dev_ifsioc+0x250/0xed0 net/core/dev_ioctl.c:334
 dev_ioctl+0x4c8/0xc8c net/core/dev_ioctl.c:588
 sock_do_ioctl+0x18c/0x240 net/socket.c:1218
 sock_ioctl+0x5c4/0x840 net/socket.c:1321
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl fs/ioctl.c:856 [inline]
 __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:856
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204
 el0_svc+0x58/0x138 arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585