INFO: task syz-executor.4:10561 can't die for more than 143 seconds.
task:syz-executor.4  state:R  running task     stack:27176 pid:10561 ppid:  8994 flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5000 [inline]
 __schedule+0xab2/0x4db0 kernel/sched/core.c:6309
 preempt_schedule_common+0x45/0xc0 kernel/sched/core.c:6474
 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:35
 __local_bh_enable_ip+0x109/0x120 kernel/softirq.c:390
 local_bh_enable include/linux/bottom_half.h:33 [inline]
 rcu_read_unlock_bh include/linux/rcupdate.h:764 [inline]
 __dev_queue_xmit+0x1950/0x3760 net/core/dev.c:4143
 pppoe_sendmsg+0x5ce/0x750 drivers/net/ppp/pppoe.c:900
 sock_sendmsg_nosec net/socket.c:705 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:725
 ____sys_sendmsg+0x331/0x810 net/socket.c:2413
 ___sys_sendmsg+0xf3/0x170 net/socket.c:2467
 __sys_sendmmsg+0x195/0x470 net/socket.c:2553
 __do_sys_sendmmsg net/socket.c:2582 [inline]
 __se_sys_sendmmsg net/socket.c:2579 [inline]
 __x64_sys_sendmmsg+0x99/0x100 net/socket.c:2579
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f684695a059
RSP: 002b:00007f68458cf168 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 00007f6846a6cf60 RCX: 00007f684695a059
RDX: 04000000000000eb RSI: 000000002000d180 RDI: 0000000000000004
RBP: 00007f68469b408d R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffe89ed895f R14: 00007f68458cf300 R15: 0000000000022000
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/27:
 #0: ffffffff8bb83960 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6463
2 locks held by getty/3277:
 #0: ffff88814b010098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:244
 #1: ffffc90002b632e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xcf0/0x1230 drivers/tty/n_tty.c:2077
1 lock held by syz-executor.4/10561:

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