INFO: task syz.9.4193:20124 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.9.4193 state:D stack:26632 pid:20124 tgid:20119 ppid:11272 task_flags:0x400548 flags:0x00080001
Call Trace:
context_switch kernel/sched/core.c:5325 [inline]
__schedule+0x16f3/0x4c20 kernel/sched/core.c:6929
__schedule_loop kernel/sched/core.c:7011 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7026
schedule_timeout+0x9a/0x270 kernel/time/sleep_timeout.c:75
do_wait_for_common kernel/sched/completion.c:100 [inline]
__wait_for_common kernel/sched/completion.c:121 [inline]
wait_for_common kernel/sched/completion.c:132 [inline]
wait_for_completion+0x2bf/0x5d0 kernel/sched/completion.c:153
io_wq_exit_workers io_uring/io-wq.c:1327 [inline]
io_wq_put_and_exit+0x316/0x650 io_uring/io-wq.c:1355
io_uring_clean_tctx+0x11f/0x1a0 io_uring/tctx.c:203
io_uring_cancel_generic+0x6ca/0x7d0 io_uring/io_uring.c:3327
io_uring_files_cancel include/linux/io_uring.h:19 [inline]
do_exit+0x345/0x2300 kernel/exit.c:912
do_group_exit+0x21c/0x2d0 kernel/exit.c:1107
get_signal+0x125d/0x1310 kernel/signal.c:3034
arch_do_signal_or_restart+0xa0/0x790 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop+0x72/0x130 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+0x2bd/0xfa0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1b4e82efc9
RSP: 002b:00007f1b4ca75038 EFLAGS: 00000246 ORIG_RAX: 00000000000001aa
RAX: 0000000000001000 RBX: 00007f1b4ea86090 RCX: 00007f1b4e82efc9
RDX: 0000000000000000 RSI: 00000000000047ba RDI: 0000000000000007
RBP: 00007f1b4e8b1f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000028 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1b4ea86128 R14: 00007f1b4ea86090 R15: 00007fffe077d128
Showing all locks held in the system:
1 lock held by khungtaskd/38:
#0: ffffffff8d5aa4c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8d5aa4c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8d5aa4c0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
5 locks held by kworker/u8:3/58:
2 locks held by getty/5559:
#0: ffff88823bf2e0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90003e762e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x444/0x1400 drivers/tty/n_tty.c:2222
5 locks held by kworker/u8:16/20498:
4 locks held by syz.8.4515/21314:
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Call Trace:
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:332 [inline]
watchdog+0xf60/0xfa0 kernel/hung_task.c:495
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 58 Comm: kworker/u8:3 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Workqueue: events_unbound nsim_dev_trap_report_work
RIP: 0010:debug_lockdep_rcu_enabled+0x21/0x40 kernel/rcu/update.c:321
Code: 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 31 c0 83 3d 97 e1 15 04 00 74 1e 83 3d 6a f0 15 04 00 74 15 65 48 8b 0c 25 08 40 a2 91 <31> c0 83 b9 5c 0b 00 00 00 0f 94 c0 e9 4e b6 03 00 cc cc cc cc cc
RSP: 0018:ffffc9000124f6f8 EFLAGS: 00000202
RAX: 0000000000000000 RBX: ffffc9000124f748 RCX: ffff888019b80000
RDX: 0000000000000000 RSI: ffffffff8cf62f13 RDI: ffffffff8b3ddbe0
RBP: ffffc9000124f7b8 R08: 0000000000000000 R09: ffffffff8ac28b41
R10: dffffc0000000000 R11: fffffbfff1dac52f R12: 1ffff92000249ee9
R13: dffffc0000000000 R14: ffff8880b8845a50 R15: ffffc9000124f740
FS: 0000000000000000(0000) GS:ffff888126dfc000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000020000022e030 CR3: 000000006ff3a000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 000000000000000e DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
rcu_read_lock include/linux/rcupdate.h:868 [inline]
__rt_spin_lock kernel/locking/spinlock_rt.c:50 [inline]
rt_spin_lock+0x1e6/0x3e0 kernel/locking/spinlock_rt.c:57
spin_lock include/linux/spinlock_rt.h:44 [inline]
___slab_alloc+0x12f/0x13f0 mm/slub.c:4516
__slab_alloc+0xc6/0x1f0 mm/slub.c:4770
__slab_alloc_node mm/slub.c:4846 [inline]
slab_alloc_node mm/slub.c:5268 [inline]
kmem_cache_alloc_node_noprof+0x1ac/0x6e0 mm/slub.c:5332
__alloc_skb+0x112/0x2d0 net/core/skbuff.c:660
alloc_skb include/linux/skbuff.h:1383 [inline]
nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:763 [inline]
nsim_dev_trap_report drivers/net/netdevsim/dev.c:820 [inline]
nsim_dev_trap_report_work+0x29f/0xbc0 drivers/net/netdevsim/dev.c:866
process_one_work kernel/workqueue.c:3263 [inline]
process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245