INFO: task syz-executor.5:8726 can't die for more than 143 seconds.
task:syz-executor.5  state:R  running task     stack:26832 pid: 8726 ppid: 31083 flags:0x00004006
Call Trace:
 context_switch kernel/sched/core.c:4955 [inline]
 __schedule+0x940/0x26f0 kernel/sched/core.c:6302
 preempt_schedule_common+0x45/0xc0 kernel/sched/core.c:6474
 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:35
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:161 [inline]
 _raw_spin_unlock_irqrestore+0x57/0x70 kernel/locking/spinlock.c:194
 spin_unlock_irqrestore include/linux/spinlock.h:423 [inline]
 prepare_to_wait_event+0xc8/0x690 kernel/sched/wait.c:325
 p9_client_rpc+0x405/0x1240 net/9p/client.c:761

Showing all locks held in the system:
1 lock held by ksoftirqd/0/13:
1 lock held by khungtaskd/26:
 #0: ffffffff8b97fce0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6446
1 lock held by in:imklog/6482:
 #0: ffff888011ee6af0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:990
3 locks held by kworker/u4:7/13038:
6 locks held by kworker/0:21/26107:
 #0: ffff8880b9c31a58 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:474 [inline]
 #0: ffff8880b9c31a58 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock kernel/sched/sched.h:1319 [inline]
 #0: ffff8880b9c31a58 (&rq->__lock){-.-.}-{2:2}, at: rq_lock kernel/sched/sched.h:1622 [inline]
 #0: ffff8880b9c31a58 (&rq->__lock){-.-.}-{2:2}, at: __schedule+0x236/0x26f0 kernel/sched/core.c:6216
 #1: ffff8880b9c1f9c8 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: process_one_work+0x8ca/0x1690 kernel/workqueue.c:2272
 #2: ffff88807b70ac18 (&clnt->lock){+.+.}-{2:2}, at: spin_lock include/linux/spinlock.h:368 [inline]
 #2: ffff88807b70ac18 (&clnt->lock){+.+.}-{2:2}, at: p9_read_work+0x97d/0x1010 net/9p/trans_fd.c:363
 #3: ffff88802683e428 (&req->wq){....}-{2:2}, at: __wake_up_common_lock+0xb4/0x130 kernel/sched/wait.c:137
 #4: ffff8880764e5eb8 (&p->pi_lock){-.-.}-{2:2}, at: debug_object_activate+0x12e/0x3e0 lib/debugobjects.c:661
 #5: ffffffff904c4638 (&obj_hash[i].lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:474 [inline]
 #5: ffffffff904c4638 (&obj_hash[i].lock){-.-.}-{2:2}, at: raw_spin_rq_lock kernel/sched/sched.h:1319 [inline]
 #5: ffffffff904c4638 (&obj_hash[i].lock){-.-.}-{2:2}, at: rq_lock kernel/sched/sched.h:1622 [inline]
 #5: ffffffff904c4638 (&obj_hash[i].lock){-.-.}-{2:2}, at: ttwu_queue kernel/sched/core.c:3772 [inline]
 #5: ffffffff904c4638 (&obj_hash[i].lock){-.-.}-{2:2}, at: try_to_wake_up+0x49f/0x1350 kernel/sched/core.c:4097
2 locks held by kworker/u4:14/4125:
2 locks held by syz-executor.2/8692:
2 locks held by syz-executor.0/8716:
2 locks held by syz-executor.5/8726:
2 locks held by syz-executor.3/8747:
2 locks held by syz-executor.4/8764:

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