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INFO: task hung in addrconf_verify_work (3)

Status: auto-closed as invalid on 2021/07/11 07:19
Reported-by: syzbot+b56bbef44c70901434a2@syzkaller.appspotmail.com
First crash: 1138d, last: 1138d
▶ ▼ Similar bugs (20)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-49 INFO: task hung in addrconf_verify_work 18 1665d 1837d 0/3 auto-closed as invalid on 2020/01/31 12:44
linux-6.1 INFO: task hung in addrconf_verify_work (2) 3 40d 86d 0/3 upstream: reported on 2024/01/29 22:05
linux-4.19 INFO: task hung in addrconf_verify_work (5) 3 651d 691d 0/1 auto-obsoleted due to no activity on 2022/11/10 09:18
linux-4.19 INFO: task hung in addrconf_verify_work (6) C error 4 433d 492d 0/1 upstream: reported C repro on 2022/12/19 15:22
linux-4.19 INFO: task hung in addrconf_verify_work (4) 6 833d 919d 0/1 auto-closed as invalid on 2022/05/13 00:19
linux-4.14 INFO: task hung in addrconf_verify_work (2) C error 7 431d 1274d 0/1 upstream: reported C repro on 2020/10/28 05:47
upstream INFO: task hung in addrconf_verify_work (2) net C 22 1654d 1654d 13/26 fixed on 2019/11/04 14:50
linux-4.19 INFO: task hung in addrconf_verify_work (2) 2 1278d 1368d 0/1 auto-closed as invalid on 2021/02/21 08:05
android-414 INFO: task hung in addrconf_verify_work C 6 1654d 1840d 0/1 public: reported C repro on 2019/04/12 00:01
upstream INFO: task hung in addrconf_verify_work (8) net C error 64 17d 128d 0/26 upstream: reported C repro on 2023/12/18 14:44
android-44 INFO: task hung in addrconf_verify_work 3 2171d 2200d 0/2 auto-closed as invalid on 2019/02/22 14:29
linux-4.19 INFO: task hung in addrconf_verify_work 1 1498d 1498d 0/1 auto-closed as invalid on 2020/07/16 23:17
upstream INFO: task hung in addrconf_verify_work (3) C done 75 1268d 1302d 15/26 fixed on 2020/11/16 12:12
upstream INFO: task hung in addrconf_verify_work (5) net C done done 68 846d 938d 0/26 closed as invalid on 2022/02/01 17:39
upstream INFO: task hung in addrconf_verify_work (7) netfilter C error 64 147d 294d 0/26 closed as invalid on 2023/12/01 14:19
linux-6.1 INFO: task hung in addrconf_verify_work 2 356d 407d 0/3 auto-obsoleted due to no activity on 2023/08/23 09:09
linux-4.14 INFO: task hung in addrconf_verify_work 4 1423d 1495d 0/1 auto-closed as invalid on 2020/09/29 04:19
upstream INFO: task hung in addrconf_verify_work net C 2 2221d 2221d 0/26 closed as invalid on 2018/03/27 11:14
upstream INFO: task hung in addrconf_verify_work (4) C done 132 1159d 1247d 20/26 fixed on 2021/04/09 19:46
upstream INFO: task hung in addrconf_verify_work (6) C done 86 429d 666d 22/26 fixed on 2023/02/24 13:51

Sample crash report:
ieee802154 phy0 wpan0: encryption failed: -22
ieee802154 phy1 wpan1: encryption failed: -22
Bluetooth: hci0: command 0x0406 tx timeout
ieee802154 phy0 wpan0: encryption failed: -22
ieee802154 phy1 wpan1: encryption failed: -22
INFO: task kworker/1:1:25 blocked for more than 140 seconds.
      Not tainted 4.19.180-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kworker/1:1     D25216    25      2 0x80000000
Workqueue: ipv6_addrconf addrconf_verify_work
Call Trace:
 context_switch kernel/sched/core.c:2828 [inline]
 __schedule+0x887/0x2040 kernel/sched/core.c:3517
 schedule+0x8d/0x1b0 kernel/sched/core.c:3561
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3619
 __mutex_lock_common kernel/locking/mutex.c:1002 [inline]
 __mutex_lock+0x647/0x1260 kernel/locking/mutex.c:1072
 addrconf_verify_work+0xa/0x20 net/ipv6/addrconf.c:4476
 process_one_work+0x864/0x1570 kernel/workqueue.c:2152
 worker_thread+0x64c/0x1130 kernel/workqueue.c:2295
 kthread+0x33f/0x460 kernel/kthread.c:259
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415
INFO: task kworker/1:4:9096 blocked for more than 140 seconds.
      Not tainted 4.19.180-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kworker/1:4     D26280  9096      2 0x80000000
Workqueue: events linkwatch_event
Call Trace:
 context_switch kernel/sched/core.c:2828 [inline]
 __schedule+0x887/0x2040 kernel/sched/core.c:3517
 schedule+0x8d/0x1b0 kernel/sched/core.c:3561
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3619
 __mutex_lock_common kernel/locking/mutex.c:1002 [inline]
 __mutex_lock+0x647/0x1260 kernel/locking/mutex.c:1072
 linkwatch_event+0xb/0x60 net/core/link_watch.c:236
 process_one_work+0x864/0x1570 kernel/workqueue.c:2152
 worker_thread+0x64c/0x1130 kernel/workqueue.c:2295
 kthread+0x33f/0x460 kernel/kthread.c:259
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415
INFO: task kworker/u4:5:9404 blocked for more than 140 seconds.
      Not tainted 4.19.180-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kworker/u4:5    D25080  9404      2 0x80000000
Workqueue: netns cleanup_net
Call Trace:
 context_switch kernel/sched/core.c:2828 [inline]
 __schedule+0x887/0x2040 kernel/sched/core.c:3517
 schedule+0x8d/0x1b0 kernel/sched/core.c:3561
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3619
 __mutex_lock_common kernel/locking/mutex.c:1002 [inline]
 __mutex_lock+0x647/0x1260 kernel/locking/mutex.c:1072
 netdev_run_todo+0x719/0xab0 net/core/dev.c:8997
 ip6_tnl_exit_batch_net+0x46a/0x660 net/ipv6/ip6_tunnel.c:2279
 ops_exit_list+0xf9/0x150 net/core/net_namespace.c:156
 cleanup_net+0x3b4/0x8b0 net/core/net_namespace.c:553
 process_one_work+0x864/0x1570 kernel/workqueue.c:2152
 worker_thread+0x64c/0x1130 kernel/workqueue.c:2295
 kthread+0x33f/0x460 kernel/kthread.c:259
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415
INFO: task syz-executor.4:31276 blocked for more than 140 seconds.
      Not tainted 4.19.180-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.4  D26584 31276  27691 0x80000002
Call Trace:
 context_switch kernel/sched/core.c:2828 [inline]
 __schedule+0x887/0x2040 kernel/sched/core.c:3517
 schedule+0x8d/0x1b0 kernel/sched/core.c:3561
 exp_funnel_lock kernel/rcu/tree_exp.h:320 [inline]
 _synchronize_rcu_expedited+0x60c/0x6f0 kernel/rcu/tree_exp.h:667
 synchronize_net net/core/dev.c:9271 [inline]
 rollback_registered_many+0xa62/0xe70 net/core/dev.c:8219
 rollback_registered+0xe9/0x1b0 net/core/dev.c:8230
 unregister_netdevice_queue+0x1de/0x3e0 net/core/dev.c:9297
 unregister_netdevice include/linux/netdevice.h:2614 [inline]
 __tun_detach+0x100d/0x1320 drivers/net/tun.c:737
 tun_detach drivers/net/tun.c:754 [inline]
 tun_chr_close+0xd9/0x180 drivers/net/tun.c:3275
 __fput+0x2ce/0x890 fs/file_table.c:278
 task_work_run+0x148/0x1c0 kernel/task_work.c:113
 exit_task_work include/linux/task_work.h:22 [inline]
 do_exit+0xbf3/0x2be0 kernel/exit.c:870
 do_group_exit+0x125/0x310 kernel/exit.c:967
 get_signal+0x3f2/0x1f70 kernel/signal.c:2589
 do_signal+0x8f/0x1670 arch/x86/kernel/signal.c:821
 exit_to_usermode_loop+0x204/0x2a0 arch/x86/entry/common.c:163
 prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:271 [inline]
 do_syscall_64+0x538/0x620 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x465f69
Code: Bad RIP value.
RSP: 002b:00007f6bda9e3218 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 000000000056c160 RCX: 0000000000465f69
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 000000000056c160
RBP: 000000000056c158 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c164
R13: 00007ffd3f2264ef R14: 00007f6bda9e3300 R15: 0000000000022000
INFO: task syz-executor.5:31369 blocked for more than 140 seconds.
      Not tainted 4.19.180-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.5  D28288 31369  27749 0x80000002
Call Trace:
 context_switch kernel/sched/core.c:2828 [inline]
 __schedule+0x887/0x2040 kernel/sched/core.c:3517
 schedule+0x8d/0x1b0 kernel/sched/core.c:3561
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3619
 __mutex_lock_common kernel/locking/mutex.c:1002 [inline]
 __mutex_lock+0x647/0x1260 kernel/locking/mutex.c:1072
 tun_detach drivers/net/tun.c:751 [inline]
 tun_chr_close+0x3a/0x180 drivers/net/tun.c:3275
 __fput+0x2ce/0x890 fs/file_table.c:278
 task_work_run+0x148/0x1c0 kernel/task_work.c:113
 exit_task_work include/linux/task_work.h:22 [inline]
 do_exit+0xbf3/0x2be0 kernel/exit.c:870
 do_group_exit+0x125/0x310 kernel/exit.c:967
 get_signal+0x3f2/0x1f70 kernel/signal.c:2589
 do_signal+0x8f/0x1670 arch/x86/kernel/signal.c:821
 exit_to_usermode_loop+0x204/0x2a0 arch/x86/entry/common.c:163
 prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:271 [inline]
 do_syscall_64+0x538/0x620 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x465f69
Code: Bad RIP value.
RSP: 002b:00007fed37764218 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 000000000056c010 RCX: 0000000000465f69
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 000000000056c010
RBP: 000000000056c008 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c014
R13: 00007fff692c380f R14: 00007fed37764300 R15: 0000000000022000
INFO: task syz-executor.0:31470 blocked for more than 140 seconds.
      Not tainted 4.19.180-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.0  D26752 31470  27693 0x80000002
Call Trace:
 context_switch kernel/sched/core.c:2828 [inline]
 __schedule+0x887/0x2040 kernel/sched/core.c:3517
 schedule+0x8d/0x1b0 kernel/sched/core.c:3561
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3619
 __mutex_lock_common kernel/locking/mutex.c:1002 [inline]
 __mutex_lock+0x647/0x1260 kernel/locking/mutex.c:1072
 tun_detach drivers/net/tun.c:751 [inline]
 tun_chr_close+0x3a/0x180 drivers/net/tun.c:3275
 __fput+0x2ce/0x890 fs/file_table.c:278
 task_work_run+0x148/0x1c0 kernel/task_work.c:113
 exit_task_work include/linux/task_work.h:22 [inline]
 do_exit+0xbf3/0x2be0 kernel/exit.c:870
 do_group_exit+0x125/0x310 kernel/exit.c:967
 get_signal+0x3f2/0x1f70 kernel/signal.c:2589
 do_signal+0x8f/0x1670 arch/x86/kernel/signal.c:821
 exit_to_usermode_loop+0x204/0x2a0 arch/x86/entry/common.c:163
 prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:271 [inline]
 do_syscall_64+0x538/0x620 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x465f69
Code: Bad RIP value.
RSP: 002b:00007ff235fb9218 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 000000000056c010 RCX: 0000000000465f69
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 000000000056c010
RBP: 000000000056c008 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c014
R13: 00007ffe4a8f727f R14: 00007ff235fb9300 R15: 0000000000022000
INFO: task syz-executor.3:32512 blocked for more than 140 seconds.
      Not tainted 4.19.180-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.3  D26584 32512  27694 0x80000002
Call Trace:
 context_switch kernel/sched/core.c:2828 [inline]
 __schedule+0x887/0x2040 kernel/sched/core.c:3517
 schedule+0x8d/0x1b0 kernel/sched/core.c:3561
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3619
 __mutex_lock_common kernel/locking/mutex.c:1002 [inline]
 __mutex_lock+0x647/0x1260 kernel/locking/mutex.c:1072
 netdev_run_todo+0x719/0xab0 net/core/dev.c:8997
 tun_detach drivers/net/tun.c:757 [inline]
 tun_chr_close+0xf5/0x180 drivers/net/tun.c:3275
 __fput+0x2ce/0x890 fs/file_table.c:278
 task_work_run+0x148/0x1c0 kernel/task_work.c:113
 exit_task_work include/linux/task_work.h:22 [inline]
 do_exit+0xbf3/0x2be0 kernel/exit.c:870
 do_group_exit+0x125/0x310 kernel/exit.c:967
 get_signal+0x3f2/0x1f70 kernel/signal.c:2589
 do_signal+0x8f/0x1670 arch/x86/kernel/signal.c:821
 exit_to_usermode_loop+0x204/0x2a0 arch/x86/entry/common.c:163
 prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:271 [inline]
 do_syscall_64+0x538/0x620 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x465f69
Code: Bad RIP value.
RSP: 002b:00007fd6cb6e0218 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 000000000056bf68 RCX: 0000000000465f69
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 000000000056bf68
RBP: 000000000056bf60 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf6c
R13: 00007ffcfb05881f R14: 00007fd6cb6e0300 R15: 0000000000022000
INFO: task syz-executor.2:2038 blocked for more than 140 seconds.
      Not tainted 4.19.180-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.2  D28648  2038      1 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2828 [inline]
 __schedule+0x887/0x2040 kernel/sched/core.c:3517
 schedule+0x8d/0x1b0 kernel/sched/core.c:3561
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3619
 __mutex_lock_common kernel/locking/mutex.c:1002 [inline]
 __mutex_lock+0x647/0x1260 kernel/locking/mutex.c:1072
 rtnl_lock net/core/rtnetlink.c:77 [inline]
 rtnetlink_rcv_msg+0x3fe/0xb80 net/core/rtnetlink.c:4775
 netlink_rcv_skb+0x160/0x440 net/netlink/af_netlink.c:2455
 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
 netlink_unicast+0x4d5/0x690 net/netlink/af_netlink.c:1344
 netlink_sendmsg+0x6bb/0xc40 net/netlink/af_netlink.c:1909
 sock_sendmsg_nosec net/socket.c:622 [inline]
 sock_sendmsg+0xc3/0x120 net/socket.c:632
 __sys_sendto+0x21a/0x320 net/socket.c:1787
 __do_sys_sendto net/socket.c:1799 [inline]
 __se_sys_sendto net/socket.c:1795 [inline]
 __x64_sys_sendto+0xdd/0x1b0 net/socket.c:1795
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4193fc
Code: Bad RIP value.
RSP: 002b:00007ffe69fe68a0 EFLAGS: 00000293 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00000000014a4320 RCX: 00000000004193fc
RDX: 0000000000000028 RSI: 00000000014a4370 RDI: 0000000000000003
RBP: 0000000000000000 R08: 00007ffe69fe68f4 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000
R13: 00000000014a4370 R14: 0000000000000003 R15: 0000000000000000

Showing all locks held in the system:
1 lock held by ksoftirqd/1/18:
 #0: 000000000ef62134 (&rq->lock){-.-.}, at: idle_balance kernel/sched/fair.c:9701 [inline]
 #0: 000000000ef62134 (&rq->lock){-.-.}, at: pick_next_task_fair+0x556/0x1570 kernel/sched/fair.c:6840
3 locks held by kworker/1:1/25:
 #0: 00000000bfe9e9b8 ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: process_one_work+0x767/0x1570 kernel/workqueue.c:2123
 #1: 00000000150c5c20 ((addr_chk_work).work){+.+.}, at: process_one_work+0x79c/0x1570 kernel/workqueue.c:2127
 #2: 000000006c1e53d0 (rtnl_mutex){+.+.}, at: addrconf_verify_work+0xa/0x20 net/ipv6/addrconf.c:4476
1 lock held by khungtaskd/1568:
 #0: 00000000cfb72b47 (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x265 kernel/locking/lockdep.c:4440
1 lock held by in:imklog/7838:
 #0: 00000000644f5057 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x26f/0x310 fs/file.c:767
3 locks held by kworker/1:4/9096:
 #0: 0000000035f3cc9d ((wq_completion)"events"){+.+.}, at: process_one_work+0x767/0x1570 kernel/workqueue.c:2123
 #1: 00000000cb9370e3 ((linkwatch_work).work){+.+.}, at: process_one_work+0x79c/0x1570 kernel/workqueue.c:2127
 #2: 000000006c1e53d0 (rtnl_mutex){+.+.}, at: linkwatch_event+0xb/0x60 net/core/link_watch.c:236
4 locks held by kworker/u4:5/9404:
 #0: 00000000f2502f67 ((wq_completion)"%s""netns"){+.+.}, at: process_one_work+0x767/0x1570 kernel/workqueue.c:2123
 #1: 00000000ff82f4ae (net_cleanup_work){+.+.}, at: process_one_work+0x79c/0x1570 kernel/workqueue.c:2127
 #2: 00000000bc42f5dd (pernet_ops_rwsem){++++}, at: cleanup_net+0xa8/0x8b0 net/core/net_namespace.c:520
 #3: 000000006c1e53d0 (rtnl_mutex){+.+.}, at: netdev_run_todo+0x719/0xab0 net/core/dev.c:8997
3 locks held by kworker/1:5/20341:
 #0: 0000000035f3cc9d ((wq_completion)"events"){+.+.}, at: process_one_work+0x767/0x1570 kernel/workqueue.c:2123
 #1: 000000004ef76f66 (deferred_process_work){+.+.}, at: process_one_work+0x79c/0x1570 kernel/workqueue.c:2127
 #2: 000000006c1e53d0 (rtnl_mutex){+.+.}, at: switchdev_deferred_process_work+0xa/0x20 net/switchdev/switchdev.c:150
1 lock held by syz-executor.4/31276:
 #0: 000000006c1e53d0 (rtnl_mutex){+.+.}, at: tun_detach drivers/net/tun.c:751 [inline]
 #0: 000000006c1e53d0 (rtnl_mutex){+.+.}, at: tun_chr_close+0x3a/0x180 drivers/net/tun.c:3275
1 lock held by syz-executor.5/31369:
 #0: 000000006c1e53d0 (rtnl_mutex){+.+.}, at: tun_detach drivers/net/tun.c:751 [inline]
 #0: 000000006c1e53d0 (rtnl_mutex){+.+.}, at: tun_chr_close+0x3a/0x180 drivers/net/tun.c:3275
1 lock held by syz-executor.0/31470:
 #0: 000000006c1e53d0 (rtnl_mutex){+.+.}, at: tun_detach drivers/net/tun.c:751 [inline]
 #0: 000000006c1e53d0 (rtnl_mutex){+.+.}, at: tun_chr_close+0x3a/0x180 drivers/net/tun.c:3275
1 lock held by syz-executor.3/32512:
 #0: 000000006c1e53d0 (rtnl_mutex){+.+.}, at: netdev_run_todo+0x719/0xab0 net/core/dev.c:8997
1 lock held by syz-executor.2/2038:
 #0: 000000006c1e53d0 (rtnl_mutex){+.+.}, at: rtnl_lock net/core/rtnetlink.c:77 [inline]
 #0: 000000006c1e53d0 (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x3fe/0xb80 net/core/rtnetlink.c:4775

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

NMI backtrace for cpu 1
CPU: 1 PID: 1568 Comm: khungtaskd Not tainted 4.19.180-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1fc/0x2ef lib/dump_stack.c:118
 nmi_cpu_backtrace.cold+0x63/0xa2 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x1a6/0x1f0 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:203 [inline]
 watchdog+0x991/0xe60 kernel/hung_task.c:287
 kthread+0x33f/0x460 kernel/kthread.c:259
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 7841 Comm: rs:main Q:Reg Not tainted 4.19.180-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:__lock_is_held+0x36/0x160 kernel/locking/lockdep.c:3720
Code: 65 4c 8b 3c 25 80 df 01 00 41 56 49 89 fe 49 8d bf 80 08 00 00 41 55 48 89 fa 41 54 48 c1 ea 03 55 53 48 83 ec 08 0f b6 04 02 <89> 74 24 04 84 c0 74 08 3c 03 0f 8e ec 00 00 00 41 8b 87 80 08 00
RSP: 0018:ffff8880976efd80 EFLAGS: 00000082
RAX: 0000000000000000 RBX: 0000000000000286 RCX: 0000000000000001
RDX: 1ffff11013e21da0 RSI: 00000000ffffffff RDI: ffff88809f10ed00
RBP: ffffffff89f85e20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffff88809f10e480
R13: ffff8880a3ba683c R14: ffffffff89f85e20 R15: ffff88809f10e480
FS:  00007fe1df414700(0000) GS:ffff8880ba000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd3bccd9000 CR3: 000000008edcb000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 lock_is_held_type+0x10d/0x210 kernel/locking/lockdep.c:3945
 lock_is_held include/linux/lockdep.h:344 [inline]
 ___might_sleep+0x1ea/0x2b0 kernel/sched/core.c:6157
 percpu_down_read_preempt_disable include/linux/percpu-rwsem.h:34 [inline]
 percpu_down_read include/linux/percpu-rwsem.h:59 [inline]
 __sb_start_write+0x4c/0x2a0 fs/super.c:1366
 file_start_write include/linux/fs.h:2779 [inline]
 vfs_write+0x463/0x540 fs/read_write.c:548
 ksys_write+0x12b/0x2a0 fs/read_write.c:599
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7fe1e1e581cd
Code: c2 20 00 00 75 10 b8 01 00 00 00 0f 05 48 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 ae fc ff ff 48 89 04 24 b8 01 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 f7 fc ff ff 48 89 d0 48 83 c4 08 48 3d 01
RSP: 002b:00007fe1df413590 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fe1d400b330 RCX: 00007fe1e1e581cd
RDX: 0000000000000403 RSI: 00007fe1d400b330 RDI: 0000000000000008
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 00007fe1d400b0b0
R13: 00007fe1df4135b0 R14: 0000557837e92440 R15: 0000000000000403

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2021/03/13 07:18 linux-4.19.y 030194a5b292 4a003785 .config console log report info ci2-linux-4-19 INFO: task hung in addrconf_verify_work
* Struck through repros no longer work on HEAD.