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INFO: task hung in namespace_unlock (2)

Status: auto-closed as invalid on 2019/10/25 14:11
Subsystems: kernel
[Documentation on labels]
First crash: 1923d, last: 1751d
▶ ▼ Similar bugs (3)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-414 INFO: task hung in namespace_unlock 1 1953d 1850d 0/1 auto-closed as invalid on 2019/06/26 03:51
upstream INFO: task hung in namespace_unlock fs 15 2129d 2138d 8/26 fixed on 2018/07/09 18:05
android-49 INFO: task hung in namespace_unlock 3 1719d 1846d 0/3 auto-closed as invalid on 2019/12/17 06:15

Sample crash report:
INFO: task syz-executor.2:10719 blocked for more than 143 seconds.
      Not tainted 5.2.0+ #61
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.2  D23944 10719      1 0x80004006
Call Trace:
 context_switch /kernel/sched/core.c:3254 [inline]
 __schedule+0x755/0x1580 /kernel/sched/core.c:3880
 schedule+0xa8/0x270 /kernel/sched/core.c:3944
 schedule_preempt_disabled+0x13/0x20 /kernel/sched/core.c:4003
 __mutex_lock_common /kernel/locking/mutex.c:1003 [inline]
 __mutex_lock+0x751/0x1340 /kernel/locking/mutex.c:1073
 mutex_lock_nested+0x16/0x20 /kernel/locking/mutex.c:1088
 exp_funnel_lock /kernel/rcu/tree_exp.h:317 [inline]
 synchronize_rcu_expedited+0x26f/0x5b0 /kernel/rcu/tree_exp.h:816
 namespace_unlock+0x108/0x130 /fs/namespace.c:1385
 drop_collected_mounts+0x82/0x90 /fs/namespace.c:1863
 put_mnt_ns /fs/namespace.c:3757 [inline]
 put_mnt_ns+0x6a/0x90 /fs/namespace.c:3753
 free_nsproxy+0x48/0x230 /kernel/nsproxy.c:172
 switch_task_namespaces+0xb3/0xd0 /kernel/nsproxy.c:225
 exit_task_namespaces+0x18/0x20 /kernel/nsproxy.c:230
 do_exit+0x92a/0x2ea0 /kernel/exit.c:876
 do_group_exit+0x135/0x360 /kernel/exit.c:981
 get_signal+0x47c/0x2500 /kernel/signal.c:2728
 do_signal+0x87/0x1670 /arch/x86/kernel/signal.c:815
 exit_to_usermode_loop+0x286/0x380 /arch/x86/entry/common.c:159
 prepare_exit_to_usermode /arch/x86/entry/common.c:194 [inline]
 syscall_return_slowpath /arch/x86/entry/common.c:274 [inline]
 do_syscall_64+0x5a9/0x6a0 /arch/x86/entry/common.c:299
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4137aa
Code: 06 00 00 00 00 bf 58 30 44 00 b9 08 00 00 00 48 89 ee f3 a6 74 2a bf 60 30 44 00 b9 09 00 00 00 48 89 ee f3 a6 75 29 48 c7 03 <50> 37 41 00 31 c0 48 83 c4 08 5b 5d c3 66 0f 1f 84 00 00 00 00 00
RSP: 002b:00007ffc8e4cc398 EFLAGS: 00000246 ORIG_RAX: 000000000000003d
RAX: fffffffffffffe00 RBX: 0000555556037940 RCX: 00000000004137aa
RDX: 0000000040000000 RSI: 00007ffc8e4cc3d0 RDI: ffffffffffffffff
RBP: 000000000000164d R08: 0000000000000001 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000007
R13: 00007ffc8e4cc3d0 R14: 000055555603799b R15: 00007ffc8e4cc3e0
INFO: task kworker/0:1:15212 blocked for more than 143 seconds.
      Not tainted 5.2.0+ #61
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kworker/0:1     D26392 15212      2 0x80004000
Workqueue: ipv6_addrconf addrconf_verify_work
Call Trace:
 context_switch /kernel/sched/core.c:3254 [inline]
 __schedule+0x755/0x1580 /kernel/sched/core.c:3880
 schedule+0xa8/0x270 /kernel/sched/core.c:3944
 schedule_preempt_disabled+0x13/0x20 /kernel/sched/core.c:4003
 __mutex_lock_common /kernel/locking/mutex.c:1003 [inline]
 __mutex_lock+0x751/0x1340 /kernel/locking/mutex.c:1073
 mutex_lock_nested+0x16/0x20 /kernel/locking/mutex.c:1088
 rtnl_lock+0x17/0x20 /net/core/rtnetlink.c:72
 addrconf_verify_work+0xe/0x20 /net/ipv6/addrconf.c:4519
 process_one_work+0x9af/0x1740 /kernel/workqueue.c:2269
 worker_thread+0x98/0xe40 /kernel/workqueue.c:2415
 kthread+0x361/0x430 /kernel/kthread.c:255
 ret_from_fork+0x24/0x30 /arch/x86/entry/entry_64.S:352

Showing all locks held in the system:
1 lock held by khungtaskd/1050:
 #0: 0000000060404c83 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e /kernel/locking/lockdep.c:5257
2 locks held by rs:main Q:Reg/10547:
1 lock held by rsyslogd/10549:
 #0: 00000000e1de0119 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 /fs/file.c:801
2 locks held by getty/10671:
 #0: 00000000da591497 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 /drivers/tty/tty_ldsem.c:341
 #1: 000000002a21c7b8 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 /drivers/tty/n_tty.c:2156
2 locks held by getty/10672:
 #0: 000000009f05d740 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 /drivers/tty/tty_ldsem.c:341
 #1: 000000003c158558 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 /drivers/tty/n_tty.c:2156
2 locks held by getty/10673:
 #0: 00000000bae93e6c (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 /drivers/tty/tty_ldsem.c:341
 #1: 0000000092f99f08 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 /drivers/tty/n_tty.c:2156
2 locks held by getty/10674:
 #0: 00000000cf100ab4 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 /drivers/tty/tty_ldsem.c:341
 #1: 00000000aecd3b28 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 /drivers/tty/n_tty.c:2156
2 locks held by getty/10675:
 #0: 000000008488e4f0 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 /drivers/tty/tty_ldsem.c:341
 #1: 00000000da3c5374 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 /drivers/tty/n_tty.c:2156
2 locks held by getty/10676:
 #0: 00000000c26c50e9 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 /drivers/tty/tty_ldsem.c:341
 #1: 000000006ac480da (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 /drivers/tty/n_tty.c:2156
2 locks held by getty/10677:
 #0: 000000005a1479b6 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 /drivers/tty/tty_ldsem.c:341
 #1: 000000009c091b69 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 /drivers/tty/n_tty.c:2156
1 lock held by syz-executor.2/10719:
 #0: 00000000e1eb0f8a (rcu_state.exp_mutex){+.+.}, at: exp_funnel_lock /kernel/rcu/tree_exp.h:317 [inline]
 #0: 00000000e1eb0f8a (rcu_state.exp_mutex){+.+.}, at: synchronize_rcu_expedited+0x26f/0x5b0 /kernel/rcu/tree_exp.h:816
3 locks held by kworker/0:1/15212:
 #0: 000000005aec598f ((wq_completion)ipv6_addrconf){+.+.}, at: __write_once_size /./include/linux/compiler.h:221 [inline]
 #0: 000000005aec598f ((wq_completion)ipv6_addrconf){+.+.}, at: arch_atomic64_set /./arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: 000000005aec598f ((wq_completion)ipv6_addrconf){+.+.}, at: atomic64_set /./include/asm-generic/atomic-instrumented.h:855 [inline]
 #0: 000000005aec598f ((wq_completion)ipv6_addrconf){+.+.}, at: atomic_long_set /./include/asm-generic/atomic-long.h:40 [inline]
 #0: 000000005aec598f ((wq_completion)ipv6_addrconf){+.+.}, at: set_work_data /kernel/workqueue.c:620 [inline]
 #0: 000000005aec598f ((wq_completion)ipv6_addrconf){+.+.}, at: set_work_pool_and_clear_pending /kernel/workqueue.c:647 [inline]
 #0: 000000005aec598f ((wq_completion)ipv6_addrconf){+.+.}, at: process_one_work+0x88b/0x1740 /kernel/workqueue.c:2240
 #1: 00000000b5dbbf5e ((addr_chk_work).work){+.+.}, at: process_one_work+0x8c1/0x1740 /kernel/workqueue.c:2244
 #2: 00000000bb01d85a (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 /net/core/rtnetlink.c:72
2 locks held by syz-executor.2/749:

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

NMI backtrace for cpu 0
CPU: 0 PID: 1050 Comm: khungtaskd Not tainted 5.2.0+ #61
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+0x172/0x1f0 /lib/dump_stack.c:113
 nmi_cpu_backtrace.cold+0x70/0xb2 /lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x23b/0x28b /lib/nmi_backtrace.c:62
 arch_trigger_cpumask_backtrace+0x14/0x20 /arch/x86/kernel/apic/hw_nmi.c:38
 trigger_all_cpu_backtrace /./include/linux/nmi.h:146 [inline]
 check_hung_uninterruptible_tasks /kernel/hung_task.c:205 [inline]
 watchdog+0x9d0/0xef0 /kernel/hung_task.c:289
 kthread+0x361/0x430 /kernel/kthread.c:255
 ret_from_fork+0x24/0x30 /arch/x86/entry/entry_64.S:352
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 21 Comm: kworker/u4:1 Not tainted 5.2.0+ #61
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: bat_events batadv_nc_worker
RIP: 0010:__rcu_read_unlock+0xea/0x130 /kernel/rcu/tree_plugin.h:403
Code: c0 75 5e 48 b8 00 00 00 00 00 fc ff df 4c 89 e2 48 c1 ea 03 0f b6 04 02 84 c0 74 04 3c 03 7e 37 c7 83 78 03 00 00 00 00 00 00 <5b> 41 5c 5d c3 0f 0b 5b 41 5c 5d c3 4c 89 e7 e8 42 54 4c 00 e9 35
RSP: 0018:ffff8880a9a57cc0 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffff8880a9a46580 RCX: ffffffff871b82f1
RDX: 1ffff11015348d1f RSI: ffffffff871b805f RDI: ffff8880a9a468fc
RBP: ffff8880a9a57cd0 R08: ffff8880a9a46580 R09: ffffed1015d26c84
R10: ffffed1015d26c83 R11: ffff8880ae93641b R12: ffff8880a9a468f8
R13: 000000000000000c R14: 0000000000000001 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffff600400 CR3: 00000000895b3000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 rcu_read_unlock /./include/linux/rcupdate.h:645 [inline]
 batadv_nc_purge_orig_hash /net/batman-adv/network-coding.c:411 [inline]
 batadv_nc_worker+0x208/0x760 /net/batman-adv/network-coding.c:718
 process_one_work+0x9af/0x1740 /kernel/workqueue.c:2269
 worker_thread+0x98/0xe40 /kernel/workqueue.c:2415
 kthread+0x361/0x430 /kernel/kthread.c:255
 ret_from_fork+0x24/0x30 /arch/x86/entry/entry_64.S:352

Crashes (9):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/07/18 19:18 upstream 22051d9c4a57 7bb222f7 .config console log report ci-upstream-kasan-gce-selinux-root
2019/04/24 11:14 upstream ba25b50d582f 8e3c52b1 .config console log report ci-upstream-kasan-gce-selinux-root
2019/03/15 23:47 upstream 6c83d0d5eb62 bab43553 .config console log report ci-upstream-kasan-gce-smack-root
2019/03/15 10:31 upstream f261c4e529da bab43553 .config console log report ci-upstream-kasan-gce-smack-root
2019/01/27 07:51 upstream ba6069759381 c73f090a .config console log report ci-upstream-kasan-gce-smack-root
2019/03/15 11:43 upstream f261c4e529da bab43553 .config console log report ci-upstream-kasan-gce-386
2019/04/24 09:33 linux-next 76c938fcaa4b 8e3c52b1 .config console log report ci-upstream-linux-next-kasan-gce-root
2019/03/24 09:41 linux-next e382d91f5f80 acbc5b7d .config console log report ci-upstream-linux-next-kasan-gce-root
2019/03/22 19:08 linux-next e382d91f5f80 dce6e62f .config console log report ci-upstream-linux-next-kasan-gce-root
* Struck through repros no longer work on HEAD.