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INFO: task hung in kernfs_find_and_get_ns (3)

Status: auto-obsoleted due to no activity on 2022/12/29 16:13
Subsystems: kernfs
[Documentation on labels]
First crash: 1260d, last: 1260d
▶ ▼ Similar bugs (4)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in kernfs_find_and_get_ns (5) kernfs 1 19 467d 682d 0/29 auto-obsoleted due to no activity on 2025/03/23 06:00
upstream INFO: task hung in kernfs_find_and_get_ns (4) kernfs 1 1 1179d 1179d 0/29 auto-obsoleted due to no activity on 2023/04/19 09:32
upstream INFO: task hung in kernfs_find_and_get_ns kernfs 1 2 2516d 2588d 0/29 auto-closed as invalid on 2019/10/25 09:41
upstream INFO: task hung in kernfs_find_and_get_ns (2) kernfs 1 1 1965d 1965d 0/29 auto-closed as invalid on 2021/02/14 10:17

Sample crash report:
INFO: task kworker/u4:17:20401 blocked for more than 144 seconds.
      Not tainted 6.1.0-rc1-next-20221021-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u4:17   state:D stack:26288 pid:20401 ppid:2      flags:0x00004000
Workqueue: netns cleanup_net
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5191 [inline]
 __schedule+0xae9/0x53f0 kernel/sched/core.c:6503
 schedule+0xda/0x1b0 kernel/sched/core.c:6579
 rwsem_down_read_slowpath+0x59f/0xb10 kernel/locking/rwsem.c:1095
 __down_read_common kernel/locking/rwsem.c:1260 [inline]
 __down_read kernel/locking/rwsem.c:1269 [inline]
 down_read+0xe2/0x450 kernel/locking/rwsem.c:1511
 kernfs_find_and_get_ns+0x6f/0xc0 fs/kernfs/dir.c:873
 kernfs_find_and_get include/linux/kernfs.h:597 [inline]
 sysfs_unmerge_group+0x5d/0x160 fs/sysfs/group.c:365
 dpm_sysfs_remove+0x88/0xb0 drivers/base/power/sysfs.c:836
 device_del+0x20b/0xc80 drivers/base/core.c:3681
 remove_one_compat_dev drivers/infiniband/core/device.c:1003 [inline]
 rdma_dev_exit_net+0x2ba/0x550 drivers/infiniband/core/device.c:1140
 ops_exit_list+0xb0/0x170 net/core/net_namespace.c:162
 cleanup_net+0x4ea/0xb00 net/core/net_namespace.c:594
 process_one_work+0x9bf/0x1710 kernel/workqueue.c:2289
 worker_thread+0x665/0x1080 kernel/workqueue.c:2436
 kthread+0x2e4/0x3a0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
 </TASK>
INFO: task syz-executor.2:20026 blocked for more than 144 seconds.
      Not tainted 6.1.0-rc1-next-20221021-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.2  state:D stack:26792 pid:20026 ppid:14071  flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5191 [inline]
 __schedule+0xae9/0x53f0 kernel/sched/core.c:6503
 schedule+0xda/0x1b0 kernel/sched/core.c:6579
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6638
 __mutex_lock_common kernel/locking/mutex.c:679 [inline]
 __mutex_lock+0xa44/0x1350 kernel/locking/mutex.c:747
 ppp_exit_net+0x17f/0x590 drivers/net/ppp/ppp_generic.c:1129
 ops_exit_list+0xb0/0x170 net/core/net_namespace.c:162
 setup_net+0x7fb/0xc50 net/core/net_namespace.c:348
 copy_net_ns+0x318/0x760 net/core/net_namespace.c:471
 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110
 copy_namespaces+0x3af/0x4a0 kernel/nsproxy.c:179
 copy_process+0x30e5/0x7230 kernel/fork.c:2250
 kernel_clone+0xe7/0x980 kernel/fork.c:2667
 __do_sys_clone+0xba/0x100 kernel/fork.c:2808
 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+0x63/0xcd
RIP: 0033:0x7fa811a8b5f9
RSP: 002b:00007fa812b45118 EFLAGS: 00000206 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007fa811babf80 RCX: 00007fa811a8b5f9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000e22c1000
RBP: 00007fa811ae67b0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007ffef95015ef R14: 00007fa812b45300 R15: 0000000000022000
 </TASK>
INFO: task syz-executor.3:20034 blocked for more than 144 seconds.
      Not tainted 6.1.0-rc1-next-20221021-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.3  state:D stack:26056 pid:20034 ppid:3618   flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5191 [inline]
 __schedule+0xae9/0x53f0 kernel/sched/core.c:6503
 schedule+0xda/0x1b0 kernel/sched/core.c:6579
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6638
 __mutex_lock_common kernel/locking/mutex.c:679 [inline]
 __mutex_lock+0xa44/0x1350 kernel/locking/mutex.c:747
 ip_tunnel_delete_nets+0x8e/0x5b0 net/ipv4/ip_tunnel.c:1121
 ops_exit_list+0x125/0x170 net/core/net_namespace.c:167
 setup_net+0x7fb/0xc50 net/core/net_namespace.c:348
 copy_net_ns+0x318/0x760 net/core/net_namespace.c:471
 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110
 copy_namespaces+0x3af/0x4a0 kernel/nsproxy.c:179
 copy_process+0x30e5/0x7230 kernel/fork.c:2250
 kernel_clone+0xe7/0x980 kernel/fork.c:2667
 __do_sys_clone+0xba/0x100 kernel/fork.c:2808
 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+0x63/0xcd
RIP: 0033:0x7f2d7a08b5f9
RSP: 002b:00007f2d7b138118 EFLAGS: 00000206 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007f2d7a1abf80 RCX: 00007f2d7a08b5f9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000e22c1000
RBP: 00007f2d7a0e67b0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007ffdc1e5a2cf R14: 00007f2d7b138300 R15: 0000000000022000
 </TASK>
INFO: task syz-executor.0:20046 blocked for more than 145 seconds.
      Not tainted 6.1.0-rc1-next-20221021-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.0  state:D stack:26368 pid:20046 ppid:3614   flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5191 [inline]
 __schedule+0xae9/0x53f0 kernel/sched/core.c:6503
 schedule+0xda/0x1b0 kernel/sched/core.c:6579
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6638
 __mutex_lock_common kernel/locking/mutex.c:679 [inline]
 __mutex_lock+0xa44/0x1350 kernel/locking/mutex.c:747
 sit_exit_batch_net+0x88/0x750 net/ipv6/sit.c:1879
 ops_exit_list+0x125/0x170 net/core/net_namespace.c:167
 setup_net+0x7fb/0xc50 net/core/net_namespace.c:348
 copy_net_ns+0x318/0x760 net/core/net_namespace.c:471
 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110
 copy_namespaces+0x3af/0x4a0 kernel/nsproxy.c:179
 copy_process+0x30e5/0x7230 kernel/fork.c:2250
 kernel_clone+0xe7/0x980 kernel/fork.c:2667
 __do_sys_clone+0xba/0x100 kernel/fork.c:2808
 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+0x63/0xcd
RIP: 0033:0x7f4fed88b5f9
RSP: 002b:00007f4feea57118 EFLAGS: 00000206 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007f4fed9abf80 RCX: 00007f4fed88b5f9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000e22c1000
RBP: 00007f4fed8e67b0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007fff6f6a7d0f R14: 00007f4feea57300 R15: 0000000000022000
 </TASK>
INFO: task syz-executor.5:20055 blocked for more than 145 seconds.
      Not tainted 6.1.0-rc1-next-20221021-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.5  state:D stack:26448 pid:20055 ppid:12597  flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5191 [inline]
 __schedule+0xae9/0x53f0 kernel/sched/core.c:6503
 schedule+0xda/0x1b0 kernel/sched/core.c:6579
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6638
 __mutex_lock_common kernel/locking/mutex.c:679 [inline]
 __mutex_lock+0xa44/0x1350 kernel/locking/mutex.c:747
 add_one_compat_dev drivers/infiniband/core/device.c:943 [inline]
 add_one_compat_dev+0xea/0x830 drivers/infiniband/core/device.c:920
 rdma_dev_init_net+0x2b5/0x4b0 drivers/infiniband/core/device.c:1185
 ops_init+0xaf/0x470 net/core/net_namespace.c:134
 setup_net+0x5d1/0xc50 net/core/net_namespace.c:325
 copy_net_ns+0x318/0x760 net/core/net_namespace.c:471
 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110
 copy_namespaces+0x3af/0x4a0 kernel/nsproxy.c:179
 copy_process+0x30e5/0x7230 kernel/fork.c:2250
 kernel_clone+0xe7/0x980 kernel/fork.c:2667
 __do_sys_clone+0xba/0x100 kernel/fork.c:2808
 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+0x63/0xcd
RIP: 0033:0x7fbf1548b5f9
RSP: 002b:00007fbf166be118 EFLAGS: 00000206 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007fbf155abf80 RCX: 00007fbf1548b5f9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000e22c1000
RBP: 00007fbf154e67b0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007ffcad3356df R14: 00007fbf166be300 R15: 0000000000022000
 </TASK>
INFO: lockdep is turned off.
NMI backtrace for cpu 1
CPU: 1 PID: 28 Comm: khungtaskd Not tainted 6.1.0-rc1-next-20221021-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/11/2022
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 nmi_cpu_backtrace.cold+0x24/0x18a lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x32f/0x3c0 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline]
 watchdog+0xc71/0xfc0 kernel/hung_task.c:377
 kthread+0x2e4/0x3a0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 20064 Comm: syz-executor.4 Not tainted 6.1.0-rc1-next-20221021-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/11/2022
RIP: 0010:kasan_depopulate_vmalloc_pte-0xc/0x70
Code: 00 48 89 fb 48 39 c7 0f 82 85 b1 84 07 eb e1 cc cc cc cc cc cc cc 48 8b 0c 24 89 f6 31 d2 e9 83 f8 ff ff 0f 1f 00 48 8b 0c 24 <89> f6 ba 01 00 00 00 e9 70 f8 ff ff 55 53 48 8b 07 48 89 fb 48 85
RSP: 0018:ffffc9000394f220 EFLAGS: 00000046
RAX: 0000000000000001 RBX: 1ffff92000729e46 RCX: ffffffff81601930
RDX: ffffed100230cf1f RSI: 0000000000000004 RDI: ffffc9000394f250
RBP: ffff8880118678f0 R08: 0000000000000001 R09: ffff8880118678f3
R10: ffffed100230cf1e R11: 000000000008c001 R12: ffff8880118678f8
R13: ffff888011867900 R14: 0000000000000004 R15: ffff8880118678f0
FS:  00007f4b483ff700(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f19e59ed6b0 CR3: 000000003bd2b000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 000000000000003b DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 instrument_atomic_read_write include/linux/instrumented.h:102 [inline]
 atomic_try_cmpxchg_acquire include/linux/atomic/atomic-instrumented.h:542 [inline]
 queued_spin_lock include/asm-generic/qspinlock.h:111 [inline]
 do_raw_spin_lock+0x120/0x2a0 kernel/locking/spinlock_debug.c:115
 rwsem_down_write_slowpath+0x653/0x12d0 kernel/locking/rwsem.c:1194
 __down_write_common kernel/locking/rwsem.c:1305 [inline]
 __down_write_common kernel/locking/rwsem.c:1302 [inline]
 __down_write kernel/locking/rwsem.c:1314 [inline]
 down_write+0x1e4/0x220 kernel/locking/rwsem.c:1563
 kernfs_add_one+0xa3/0x4e0 fs/kernfs/dir.c:738
 __kernfs_create_file+0x29c/0x350 fs/kernfs/file.c:1072
 sysfs_add_file_mode_ns+0x20f/0x3f0 fs/sysfs/file.c:294
 sysfs_merge_group+0x196/0x310 fs/sysfs/group.c:342
 dpm_sysfs_add+0x241/0x290 drivers/base/power/sysfs.c:707
 device_add+0xa82/0x1e90 drivers/base/core.c:3474
 netdev_register_kobject+0x181/0x400 net/core/net-sysfs.c:2015
 register_netdevice+0xd95/0x1670 net/core/dev.c:10057
 register_netdev+0x2d/0x50 net/core/dev.c:10183
 vti6_init_net+0x449/0x860 net/ipv6/ip6_vti.c:1164
 ops_init+0xaf/0x470 net/core/net_namespace.c:134
 setup_net+0x5d1/0xc50 net/core/net_namespace.c:325
 copy_net_ns+0x318/0x760 net/core/net_namespace.c:471
 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110
 copy_namespaces+0x3af/0x4a0 kernel/nsproxy.c:179
 copy_process+0x30e5/0x7230 kernel/fork.c:2250
 kernel_clone+0xe7/0x980 kernel/fork.c:2667
 __do_sys_clone3+0x1cd/0x2e0 kernel/fork.c:2966
 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+0x63/0xcd
RIP: 0033:0x7f4b48c8b5f9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f4b483ff038 EFLAGS: 00000246 ORIG_RAX: 00000000000001b3
RAX: ffffffffffffffda RBX: 00007f4b48dac1f0 RCX: 00007f4b48c8b5f9
RDX: 0000000000000000 RSI: 0000000000000058 RDI: 00007f4b483ff050
RBP: 00007f4b48ce67b0 R08: 0000000000000000 R09: 0000000000000058
R10: 00007f4b483ff050 R11: 0000000000000246 R12: 0000000000000058
R13: 00007fff6ed3caff R14: 00007f4b483ff300 R15: 0000000000022000
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/10/22 07:09 linux-next 4d48f589d294 c0b80a55 .config console log report info [disk image] [vmlinux] ci-upstream-linux-next-kasan-gce-root INFO: task hung in kernfs_find_and_get_ns
* Struck through repros no longer work on HEAD.