INFO: task syz.5.4809:23384 blocked for more than 143 seconds.
      Not tainted syzkaller #0
      Blocked by coredump.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.4809      state:D stack:26440 pid:23384 tgid:23383 ppid:20993  task_flags:0x400548 flags:0x00024000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5357 [inline]
 __schedule+0x1190/0x5de0 kernel/sched/core.c:6961
 __schedule_loop kernel/sched/core.c:7043 [inline]
 schedule+0xe7/0x3a0 kernel/sched/core.c:7058
 schedule_timeout+0x257/0x290 kernel/time/sleep_timeout.c:75
 do_wait_for_common kernel/sched/completion.c:100 [inline]
 __wait_for_common+0x2fc/0x4e0 kernel/sched/completion.c:121
 io_wq_exit_workers io_uring/io-wq.c:1327 [inline]
 io_wq_put_and_exit+0x271/0x8a0 io_uring/io-wq.c:1355
 io_uring_clean_tctx+0x10d/0x190 io_uring/tctx.c:203
 io_uring_cancel_generic+0x69c/0x9a0 io_uring/io_uring.c:3272
 io_uring_files_cancel include/linux/io_uring.h:19 [inline]
 do_exit+0x2ce/0x2bf0 kernel/exit.c:907
 do_group_exit+0xd3/0x2a0 kernel/exit.c:1102
 get_signal+0x2673/0x26d0 kernel/signal.c:3034
 arch_do_signal_or_restart+0x8f/0x7d0 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop+0x84/0x110 kernel/entry/common.c:40
 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
 do_syscall_64+0x3f6/0x4c0 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1696d8ebe9
RSP: 002b:00007f1697b580e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007f1696fb5fa8 RCX: 00007f1696d8ebe9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f1696fb5fa8
RBP: 00007f1696fb5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1696fb6038 R14: 00007ffe90458770 R15: 00007ffe90458858
 </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 lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
 nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x29c/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+0xf0e/0x1260 kernel/hung_task.c:491
 kthread+0x3c2/0x780 kernel/kthread.c:463
 ret_from_fork+0x5d7/0x6f0 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: 7014 Comm: kworker/u8:8 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Workqueue: bat_events batadv_mcast_mla_update
RIP: 0010:preempt_latency_start kernel/sched/core.c:5809 [inline]
RIP: 0010:preempt_latency_start kernel/sched/core.c:5804 [inline]
RIP: 0010:preempt_count_add+0x9e/0x150 kernel/sched/core.c:5832
Code: 0f 00 85 c0 75 38 65 48 8b 2d a6 b7 4d 12 48 8d bd e0 14 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 <0f> 85 87 00 00 00 48 89 9d e0 14 00 00 5b 5d e9 3e 08 0e 0a 31 ff
RSP: 0018:ffffc9001c14f880 EFLAGS: 00000046
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 1ffffffff35cb610
RDX: 1ffff11006a9dbac RSI: ffffffff81a73bb7 RDI: ffff8880354edd60
RBP: ffff8880354ec880 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000002c10 R12: 0000000000000001
R13: ffff888060591778 R14: ffffed100c0b22f3 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8881246bc000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000404030 CR3: 000000000e380000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:109 [inline]
 _raw_spin_lock_irqsave+0x1e/0x60 kernel/locking/spinlock.c:162
 lock_timer_base+0x127/0x1d0 kernel/time/timer.c:1004
 __mod_timer+0x425/0xd30 kernel/time/timer.c:1085
 add_timer_global+0x8a/0xc0 kernel/time/timer.c:1283
 __queue_delayed_work+0x33a/0x460 kernel/workqueue.c:2524
 queue_delayed_work_on+0x1b5/0x200 kernel/workqueue.c:2559
 queue_delayed_work include/linux/workqueue.h:684 [inline]
 batadv_mcast_start_timer net/batman-adv/multicast.c:70 [inline]
 batadv_mcast_mla_update+0x1594/0x31b0 net/batman-adv/multicast.c:947
 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3236
 process_scheduled_works kernel/workqueue.c:3319 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400
 kthread+0x3c2/0x780 kernel/kthread.c:463
 ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>