INFO: task syz.3.1988:13009 blocked for more than 143 seconds.
      Not tainted 6.15.0-rc5-syzkaller-00043-gd76bb1ebb558 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.1988      state:D stack:28312 pid:13009 tgid:13008 ppid:12174  task_flags:0x400040 flags:0x20000004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0x16e2/0x4cd0 kernel/sched/core.c:6767
 __schedule_loop kernel/sched/core.c:6845 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:6860
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917
 __mutex_lock_common kernel/locking/mutex.c:678 [inline]
 __mutex_lock+0x724/0xe80 kernel/locking/mutex.c:746
 relay_open+0x3b8/0x920 kernel/relay.c:514
 do_blk_trace_setup+0x591/0x9d0 kernel/trace/blktrace.c:590
 compat_blk_trace_setup kernel/trace/blktrace.c:667 [inline]
 blk_trace_ioctl+0x35b/0x430 kernel/trace/blktrace.c:735
 compat_blkdev_ioctl+0x442/0x780 block/ioctl.c:753
 __do_compat_sys_ioctl fs/ioctl.c:1004 [inline]
 __se_compat_sys_ioctl fs/ioctl.c:947 [inline]
 __ia32_compat_sys_ioctl+0x551/0x840 fs/ioctl.c:947
 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
 __do_fast_syscall_32+0xb4/0x110 arch/x86/entry/syscall_32.c:306
 do_fast_syscall_32+0x34/0x80 arch/x86/entry/syscall_32.c:331
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e
RIP: 0023:0xf70ee539
RSP: 002b:00000000f50de55c EFLAGS: 00000206 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000c0401273
RDX: 00000000800000c0 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/31:
 #0: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 #0: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
 #0: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6764
4 locks held by kworker/u8:2/36:
2 locks held by getty/5594:
 #0: ffff88803456a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc900033532f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
3 locks held by kworker/1:3/5833:
2 locks held by syz.0.1966/12895:
2 locks held by syz.3.1988/13009:
 #0: ffff888024bc92d8 (&q->debugfs_mutex){+.+.}-{4:4}, at: compat_blk_trace_setup kernel/trace/blktrace.c:666 [inline]
 #0: ffff888024bc92d8 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_ioctl+0x33f/0x430 kernel/trace/blktrace.c:735
 #1: ffffffff8df8ee08 (relay_channels_mutex){+.+.}-{4:4}, at: relay_open+0x3b8/0x920 kernel/relay.c:514
1 lock held by syz.5.2396/14330:
 #0: ffffffff8df41200 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3774
1 lock held by syz.6.2395/14344:

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

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc5-syzkaller-00043-gd76bb1ebb558 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/29/2025
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:158 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:274 [inline]
 watchdog+0xfee/0x1030 kernel/hung_task.c:437
 kthread+0x70e/0x8a0 kernel/kthread.c:464
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
 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: 5937 Comm: kworker/0:6 Not tainted 6.15.0-rc5-syzkaller-00043-gd76bb1ebb558 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/29/2025
Workqueue: wg-crypt-wg0 wg_packet_encrypt_worker
RIP: 0010:skb_scrub_packet+0x0/0x3d0 net/core/skbuff.c:6140
Code: 07 38 c1 0f 8c cd fc ff ff 48 89 df e8 d9 99 e6 f8 e9 c0 fc ff ff 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <f3> 0f 1e fa 55 41 57 41 56 41 55 41 54 53 50 89 74 24 04 48 89 fb
RSP: 0018:ffffc90004977598 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 000000003c79048f RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff888058197780
RBP: ffffc90004977b10 R08: ffffc900049774df R09: 0000000000000000
R10: ffffc900049774a0 R11: fffff5200092ee9c R12: dffffc0000000000
R13: 1ffff1100b032f00 R14: 1ffff1100b032f03 R15: ffff888058197780
FS:  0000000000000000(0000) GS:ffff8881260cb000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000008013b018 CR3: 000000008a3d8000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 00000000000032e7 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 wg_reset_packet drivers/net/wireguard/queueing.h:81 [inline]
 wg_packet_encrypt_worker+0x9e0/0x1720 drivers/net/wireguard/send.c:299
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xadb/0x17a0 kernel/workqueue.c:3319
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400
 kthread+0x70e/0x8a0 kernel/kthread.c:464
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
vkms_vblank_simulate: vblank timer overrun