INFO: task syz.2.506:7925 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.2.506       state:D stack:26920 pid:7925  tgid:7923  ppid:5878   task_flags:0x400548 flags:0x00080005
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5325 [inline]
 __schedule+0x1190/0x5de0 kernel/sched/core.c:6929
 __schedule_loop kernel/sched/core.c:7011 [inline]
 schedule+0xe7/0x3a0 kernel/sched/core.c:7026
 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:3327
 io_uring_files_cancel include/linux/io_uring.h:19 [inline]
 do_exit+0x2ce/0x2bf0 kernel/exit.c:912
 do_group_exit+0xd3/0x2a0 kernel/exit.c:1107
 get_signal+0x2671/0x26d0 kernel/signal.c:3034
 arch_do_signal_or_restart+0x8f/0x7c0 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop+0x85/0x130 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+0x426/0xfa0 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f700918efc9
RSP: 002b:00007f7009fbf0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007f70093e6098 RCX: 00007f700918efc9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f70093e6098
RBP: 00007f70093e6090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f70093e6128 R14: 00007ffdc4f88a00 R15: 00007ffdc4f88ae8
 </TASK>

Showing all locks held in the system:
1 lock held by pool_workqueue_/3:
 #0: ffffffff8e3cf9f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x1a3/0x3c0 kernel/rcu/tree_exp.h:343
2 locks held by kworker/u8:0/12:
1 lock held by khungtaskd/31:
 #0: ffffffff8e3c4460 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 #0: ffffffff8e3c4460 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
 #0: ffffffff8e3c4460 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6775
2 locks held by getty/5568:
 #0: ffff88814ca8c0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
 #1: ffffc900036bb2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222
2 locks held by kworker/u8:8/6250:
 #0: ffff88801efb3948 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3238
 #1: ffffc9000be7fd00 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3239
2 locks held by kworker/u8:12/8672:
 #0: ffff88801efb3948 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3238
 #1: ffffc900035d7d00 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3239
4 locks held by kworker/u8:14/8677:
 #0: ffff88801ba94948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3238
 #1: ffffc90003287d00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3239
 #2: ffffffff900d01f0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xad/0x8b0 net/core/net_namespace.c:669
 #3: ffffffff8e3cf8c0 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x48/0x6e0 kernel/rcu/tree.c:3820
1 lock held by syz.1.1039/9912:

=============================================

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 10/02/2025
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:332 [inline]
 watchdog+0xf3f/0x1170 kernel/hung_task.c:495
 kthread+0x3c5/0x780 kernel/kthread.c:463
 ret_from_fork+0x675/0x7d0 arch/x86/kernel/process.c:158
 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: 7927 Comm: iou-wrk-7925 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline]
RIP: 0010:rcu_is_watching+0xd/0xc0 kernel/rcu/tree.c:751
Code: 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 53 65 ff 05 73 88 ff 11 <e8> 5e 83 be 09 48 c7 c3 a8 92 a2 93 89 c5 83 f8 07 0f 87 82 00 00
RSP: 0018:ffffc9000fd1f6d0 EFLAGS: 00000087
RAX: 0000000000000000 RBX: ffffc9000fd1f8a0 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffc9000fd1f8a0
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000000001
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS:  00007f7009fbf6c0(0000) GS:ffff888124a0a000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000dbe000 CR3: 000000005a0ec000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 trace_lock_acquire include/trace/events/lock.h:24 [inline]
 lock_acquire+0x2cd/0x350 kernel/locking/lockdep.c:5831
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
 _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162
 complete_with_flags kernel/sched/completion.c:25 [inline]
 complete+0x1d/0x200 kernel/sched/completion.c:52
 csd_do_func kernel/smp.c:136 [inline]
 generic_exec_single+0x1c7/0x390 kernel/smp.c:439
 smp_call_function_single_async+0x68/0xd0 kernel/smp.c:732
 rdmsr_safe_on_cpu+0x104/0x210 arch/x86/lib/msr-smp.c:179
 msr_read+0x19d/0x250 arch/x86/kernel/msr.c:66
 loop_rw_iter+0x2fa/0x690 io_uring/rw.c:729
 io_iter_do_read io_uring/rw.c:836 [inline]
 io_iter_do_read io_uring/rw.c:829 [inline]
 __io_read+0x1055/0x14b0 io_uring/rw.c:951
 io_read+0x8d/0x1f0 io_uring/rw.c:1031
 __io_issue_sqe+0xe8/0x7c0 io_uring/io_uring.c:1824
 io_issue_sqe+0x85/0x1000 io_uring/io_uring.c:1847
 io_wq_submit_work+0x3b8/0xac0 io_uring/io_uring.c:1959
 io_worker_handle_work+0x639/0x16f0 io_uring/io-wq.c:650
 io_wq_worker+0x35f/0xdd0 io_uring/io-wq.c:704
 ret_from_fork+0x675/0x7d0 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
vkms_vblank_simulate: vblank timer overrun
vkms_vblank_simulate: vblank timer overrun
vkms_vblank_simulate: vblank timer overrun
vkms_vblank_simulate: vblank timer overrun
vkms_vblank_simulate: vblank timer overrun
vkms_vblank_simulate: vblank timer overrun
vkms_vblank_simulate: vblank timer overrun
ip6_tunnel: ip6gre1 xmit: Local address not yet configured!