syzbot

INFO: task kworker/0:7:4248 blocked for more than 142 seconds.
      Not tainted 5.15.174-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:7     state:D stack:23232 pid: 4248 ppid:     2 flags:0x00004000
Workqueue: events nsim_dev_trap_report_work
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5027 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373
 schedule+0x11b/0x1f0 kernel/sched/core.c:6456
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6515
 __mutex_lock_common+0xe34/0x25a0 kernel/locking/mutex.c:669
 __mutex_lock kernel/locking/mutex.c:729 [inline]
 mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
 nsim_dev_trap_report_work+0x56/0xab0 drivers/net/netdevsim/dev.c:757
 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>

Showing all locks held in the system:
3 locks held by kworker/1:1/23:
1 lock held by khungtaskd/27:
 #0: ffffffff8cb1fd20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
2 locks held by kworker/u4:2/154:
8 locks held by kworker/u4:3/601:
 #0: ffff8880175cd938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
 #1: ffffc9000363fd20 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
 #2: ffffffff8dc35d90 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0xf1/0xb60 net/core/net_namespace.c:561
 #3: ffffffff8dc67068 (devlink_mutex){+.+.}-{3:3}, at: devlink_pernet_pre_exit+0xb1/0x350 net/core/devlink.c:11534
 #4: ffff88807dc3e658 (&nsim_bus_dev->nsim_bus_reload_lock){+.+.}-{3:3}, at: nsim_dev_reload_down+0x58/0x160 drivers/net/netdevsim/dev.c:870
 #5: ffff88807dc3f400 (&nsim_dev->port_list_lock){+.+.}-{3:3}, at: nsim_dev_port_del_all drivers/net/netdevsim/dev.c:1359 [inline]
 #5: ffff88807dc3f400 (&nsim_dev->port_list_lock){+.+.}-{3:3}, at: nsim_dev_reload_destroy+0x118/0x240 drivers/net/netdevsim/dev.c:1561
 #6: ffffffff8dc41988 (rtnl_mutex){+.+.}-{3:3}, at: nsim_destroy+0x3a/0x140 drivers/net/netdevsim/netdev.c:381
 #7: ffffffff8cb242e8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline]
 #7: ffffffff8cb242e8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x280/0x740 kernel/rcu/tree_exp.h:845
2 locks held by getty/3939:
 #0: ffff88802be53098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
 #1: ffffc900025ae2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6af/0x1db0 drivers/tty/n_tty.c:2158
3 locks held by kworker/0:7/4248:
 #0: ffff888017470938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
 #1: ffffc9000325fd20 ((work_completion)(&(&nsim_dev->trap_data->trap_report_dw)->work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
 #2: ffff88807dc3f400 (&nsim_dev->port_list_lock){+.+.}-{3:3}, at: nsim_dev_trap_report_work+0x56/0xab0 drivers/net/netdevsim/dev.c:757
2 locks held by syz.2.14/4284:
 #0: ffffffff8dc35d90 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x378/0x5d0 net/core/net_namespace.c:472
 #1: ffffffff8dc67068 (devlink_mutex){+.+.}-{3:3}, at: devlink_pernet_pre_exit+0xb1/0x350 net/core/devlink.c:11534
1 lock held by syz.4.23/4298:
 #0: ffffffff8dc41988 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:699 [inline]
 #0: ffffffff8dc41988 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3a/0x1b0 drivers/net/tun.c:3440
1 lock held by syz-executor/4304:
 #0: ffffffff8dc41988 (rtnl_mutex){+.+.}-{3:3}, at: netdev_run_todo+0xa4f/0xc40 net/core/dev.c:10664
2 locks held by syz-executor/4307:
 #0: ffffffff8dc35d90 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x378/0x5d0 net/core/net_namespace.c:472
 #1: ffffffff8dc67068 (devlink_mutex){+.+.}-{3:3}, at: devlink_pernet_pre_exit+0xb1/0x350 net/core/devlink.c:11534
1 lock held by syz-executor/4335:
 #0: ffffffff8dc41988 (rtnl_mutex){+.+.}-{3:3}, at: netdev_run_todo+0xa4f/0xc40 net/core/dev.c:10664
1 lock held by syz-executor/4340:
 #0: ffffffff8dc41988 (rtnl_mutex){+.+.}-{3:3}, at: netdev_run_todo+0xa4f/0xc40 net/core/dev.c:10664
1 lock held by syz-executor/4342:
 #0: ffffffff8dc41988 (rtnl_mutex){+.+.}-{3:3}, at: netdev_run_todo+0xa4f/0xc40 net/core/dev.c:10664
1 lock held by syz-executor/4344:
 #0: ffffffff8dc41988 (rtnl_mutex){+.+.}-{3:3}, at: netdev_run_todo+0xa4f/0xc40 net/core/dev.c:10664
1 lock held by syz-executor/4347:
 #0: ffffffff8dc41988 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:699 [inline]
 #0: ffffffff8dc41988 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3a/0x1b0 drivers/net/tun.c:3440
1 lock held by syz-executor/4369:
 #0: ffffffff8dc41988 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
 #0: ffffffff8dc41988 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x94c/0xee0 net/core/rtnetlink.c:5644
1 lock held by syz-executor/4377:
 #0: ffffffff8dc41988 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
 #0: ffffffff8dc41988 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x94c/0xee0 net/core/rtnetlink.c:5644
1 lock held by syz-executor/4381:
 #0: ffffffff8dc41988 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
 #0: ffffffff8dc41988 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x94c/0xee0 net/core/rtnetlink.c:5644
1 lock held by syz-executor/4383:
 #0: ffffffff8dc41988 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
 #0: ffffffff8dc41988 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x94c/0xee0 net/core/rtnetlink.c:5644
2 locks held by syz-executor/4392:
 #0: ffffffff8dc35d90 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x378/0x5d0 net/core/net_namespace.c:472
 #1: ffffffff8dc41988 (rtnl_mutex){+.+.}-{3:3}, at: wg_netns_pre_exit+0x1b/0x1d0 drivers/net/wireguard/device.c:404

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

NMI backtrace for cpu 1
CPU: 1 PID: 27 Comm: khungtaskd Not tainted 5.15.174-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/25/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline]
 watchdog+0xe72/0xeb0 kernel/hung_task.c:295
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 13 Comm: kworker/0:1 Not tainted 5.15.174-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/25/2024
Workqueue: events nsim_dev_trap_report_work
RIP: 0010:trace_hardirqs_on+0x57/0x80 kernel/trace/trace_preemptirq.c:46
Code: 84 f9 ff 81 e3 00 00 f0 00 74 0e e8 73 81 f9 ff eb 18 e8 6c 81 f9 ff eb 1c e8 65 81 f9 ff 48 8b 7c 24 08 31 f6 e8 29 00 00 00 <65> c7 05 26 2f 7c 7e 00 00 00 00 e8 89 91 db ff 48 8b 7c 24 08 5b
RSP: 0018:ffffc90000d278b0 EFLAGS: 00000093
RAX: ffffffff818703c8 RBX: 0000000000000000 RCX: ffff88813ff20000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff84891f84
RBP: ffffc90000d27a10 R08: ffffffff81870360 R09: fffffbfff1c14c06
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000200
R13: dffffc0000000000 R14: ffffc90000d27980 R15: 1ffff920001a4f20
FS:  0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f499bc15f98 CR3: 000000002ca30000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 crng_make_state+0x3b4/0x690 drivers/char/random.c:392
 _get_random_bytes+0xd3/0x2b0 drivers/char/random.c:405
 nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:691 [inline]
 nsim_dev_trap_report drivers/net/netdevsim/dev.c:721 [inline]
 nsim_dev_trap_report_work+0x64e/0xab0 drivers/net/netdevsim/dev.c:762
 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>