INFO: task syz-executor:24722 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:22760 pid:24722 tgid:24722 ppid:1      task_flags:0x400140 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5357 [inline]
 __schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
 __schedule_loop kernel/sched/core.c:7043 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:7058
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7115
 __mutex_lock_common kernel/locking/mutex.c:676 [inline]
 __mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:760
 del_device_store+0xd1/0x360 drivers/net/netdevsim/bus.c:234
 kernfs_fop_write_iter+0x375/0x4f0 fs/kernfs/file.c:334
 new_sync_write fs/read_write.c:593 [inline]
 vfs_write+0x5c9/0xb30 fs/read_write.c:686
 ksys_write+0x145/0x250 fs/read_write.c:738
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa4cf18d69f
RSP: 002b:00007ffcd44b4a80 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00007fa4cf18d69f
RDX: 0000000000000001 RSI: 00007ffcd44b4ad0 RDI: 0000000000000005
RBP: 00007fa4cf2130c1 R08: 0000000000000000 R09: 00007ffcd44b48d7
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000001
R13: 00007ffcd44b4ad0 R14: 00007fa4cfee4620 R15: 0000000000000003
 </TASK>
INFO: lockdep is turned off.
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:328 [inline]
 watchdog+0xf93/0xfe0 kernel/hung_task.c:491
 kthread+0x70e/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 5865 Comm: kworker/0:3 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Workqueue: events_long defense_work_handler
RIP: 0010:chacha_init_consts include/crypto/chacha.h:72 [inline]
RIP: 0010:crng_fast_key_erasure+0xad/0x240 drivers/char/random.c:323
Code: 48 c1 e8 03 42 0f b6 04 38 84 c0 0f 85 39 01 00 00 41 c7 04 24 65 78 70 61 49 8d 7c 24 04 48 89 f8 48 c1 e8 03 42 0f b6 04 38 <84> c0 0f 85 36 01 00 00 41 c7 44 24 04 6e 64 20 33 49 8d 7c 24 08
RSP: 0018:ffffc90000006440 EFLAGS: 00000807
RAX: 0000000000000000 RBX: 1ffff92000000c8c RCX: ffff8880329f8000
RDX: 0000000000000100 RSI: ffffc90000006660 RDI: ffffc90000006664
RBP: ffffc90000006530 R08: 0000000000000001 R09: 0000000000000000
R10: ffffc900000066c0 R11: fffff52000000ce0 R12: ffffc90000006660
R13: ffff8880b8636310 R14: ffff8880b8636310 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff888125c18000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0d010dd582 CR3: 000000000df36000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 crng_make_state+0x255/0x700 drivers/char/random.c:392
 _get_random_bytes+0xd5/0x210 drivers/char/random.c:406
 get_random_u16+0x2ec/0x940 drivers/char/random.c:553
 cake_get_flow_quantum+0x18e/0x290 net/sched/sch_cake.c:687
 cake_dequeue+0x29de/0x4ab0 net/sched/sch_cake.c:2119
 dequeue_skb net/sched/sch_generic.c:294 [inline]
 qdisc_restart net/sched/sch_generic.c:399 [inline]
 __qdisc_run+0x239/0x15f0 net/sched/sch_generic.c:417
 __dev_xmit_skb net/core/dev.c:4183 [inline]
 __dev_queue_xmit+0x1056/0x3b50 net/core/dev.c:4691
 dev_queue_xmit include/linux/netdevice.h:3361 [inline]
 neigh_hh_output include/net/neighbour.h:531 [inline]
 neigh_output include/net/neighbour.h:545 [inline]
 ip_finish_output2+0xd03/0x1160 net/ipv4/ip_output.c:235
 NF_HOOK_COND include/linux/netfilter.h:307 [inline]
 ip_output+0x2a1/0x3c0 net/ipv4/ip_output.c:436
 synproxy_send_client_synack+0x8bb/0xe20 net/netfilter/nf_synproxy_core.c:484
 nft_synproxy_eval_v4+0x36e/0x560 net/netfilter/nft_synproxy.c:59
 nft_synproxy_do_eval+0x345/0x570 net/netfilter/nft_synproxy.c:141
 expr_call_ops_eval net/netfilter/nf_tables_core.c:237 [inline]
 nft_do_chain+0x409/0x1920 net/netfilter/nf_tables_core.c:285
 nft_do_chain_inet+0x25d/0x340 net/netfilter/nft_chain_filter.c:161
 nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline]
 nf_hook_slow+0xc2/0x220 net/netfilter/core.c:623
 nf_hook include/linux/netfilter.h:273 [inline]
 NF_HOOK+0x206/0x3a0 include/linux/netfilter.h:316
 NF_HOOK+0x309/0x3a0 include/linux/netfilter.h:318
 __netif_receive_skb_one_core net/core/dev.c:5991 [inline]
 __netif_receive_skb+0x143/0x380 net/core/dev.c:6104
 process_backlog+0x60e/0x14f0 net/core/dev.c:6456
 __napi_poll+0xc7/0x360 net/core/dev.c:7506
 napi_poll net/core/dev.c:7569 [inline]
 net_rx_action+0x707/0xe30 net/core/dev.c:7696
 handle_softirqs+0x283/0x870 kernel/softirq.c:579
 do_softirq+0xec/0x180 kernel/softirq.c:480
 </IRQ>
 <TASK>
 __local_bh_enable_ip+0x17d/0x1c0 kernel/softirq.c:407
 local_bh_enable include/linux/bottom_half.h:33 [inline]
 update_defense_level+0x8d2/0xd80 net/netfilter/ipvs/ip_vs_ctl.c:210
 defense_work_handler+0x2d/0xd0 net/netfilter/ipvs/ip_vs_ctl.c:235
 process_one_work kernel/workqueue.c:3236 [inline]
 process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3319
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400
 kthread+0x70e/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>