INFO: task hung in rtnl_lock

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: b98aebd2 Linux 4.14.150
git tree: linux-4.14.y
console output: https://syzkaller.appspot.com/x/log.txt?x=1354fd9ce00000
kernel config: https://syzkaller.appspot.com/x/.config?x=c52c93b368dac5a7
dashboard link: https://syzkaller.appspot.com/bug?extid=c26c776aaac86f0d33bb
compiler: gcc (GCC) 9.0.0 20181231 (experimental)

Unfortunately, I don't have any reproducer for this crash yet.

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+c26c77...@syzkaller.appspotmail.com

device bridge_slave_1 left promiscuous mode
bridge0: port 2(bridge_slave_1) entered disabled state
device bridge_slave_0 left promiscuous mode
bridge0: port 1(bridge_slave_0) entered disabled state
INFO: task kworker/1:0:31283 blocked for more than 140 seconds.
Not tainted 4.14.150 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kworker/1:0 D27584 31283 2 0x80000000
Workqueue: events linkwatch_event
Call Trace:
context_switch kernel/sched/core.c:2807 [inline]
__schedule+0x7b8/0x1cd0 kernel/sched/core.c:3383
schedule+0x92/0x1c0 kernel/sched/core.c:3427
schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3485
__mutex_lock_common kernel/locking/mutex.c:833 [inline]
__mutex_lock+0x73c/0x1470 kernel/locking/mutex.c:893
mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908
rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72
linkwatch_event+0xe/0x60 net/core/link_watch.c:236
process_one_work+0x863/0x1600 kernel/workqueue.c:2114
worker_thread+0x5d9/0x1050 kernel/workqueue.c:2248
kthread+0x319/0x430 kernel/kthread.c:232
ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404
INFO: task kworker/1:2:21571 blocked for more than 140 seconds.
Not tainted 4.14.150 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kobject: 'rx-0' (ffff8881ef9a5910): kobject_cleanup, parent ffff8881f59c1448
kworker/1:2 D29568 21571 2 0x80000000
Workqueue: events switchdev_deferred_process_work
kobject: 'rx-0' (ffff8881ef9a5910): auto cleanup 'remove' event
Call Trace:
kobject: 'rx-0' (ffff8881ef9a5910): kobject_uevent_env
context_switch kernel/sched/core.c:2807 [inline]
__schedule+0x7b8/0x1cd0 kernel/sched/core.c:3383
kobject: 'rx-0' (ffff8881ef9a5910): kobject_uevent_env: uevent_suppress
caused the event to drop!
kobject: 'rx-0' (ffff8881ef9a5910): auto cleanup kobject_del
schedule+0x92/0x1c0 kernel/sched/core.c:3427
schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3485
__mutex_lock_common kernel/locking/mutex.c:833 [inline]
__mutex_lock+0x73c/0x1470 kernel/locking/mutex.c:893
kobject: 'rx-0' (ffff8881ef9a5910): calling ktype release
kobject: 'rx-0': free name
mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908
kobject: 'tx-0' (ffff88801654cad8): kobject_cleanup, parent ffff8881f59c1448
kobject: 'tx-0' (ffff88801654cad8): auto cleanup 'remove' event
rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72
switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:150
process_one_work+0x863/0x1600 kernel/workqueue.c:2114
worker_thread+0x5d9/0x1050 kernel/workqueue.c:2248
kthread+0x319/0x430 kernel/kthread.c:232
ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404
kobject: 'tx-0' (ffff88801654cad8): kobject_uevent_env
INFO: task syz-executor.4:25978 blocked for more than 140 seconds.
kobject: 'tx-0' (ffff88801654cad8): kobject_uevent_env: uevent_suppress
caused the event to drop!
Not tainted 4.14.150 #0
kobject: 'tx-0' (ffff88801654cad8): auto cleanup kobject_del
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kobject: 'tx-0' (ffff88801654cad8): calling ktype release
syz-executor.4 D28448 25978 1 0x00000004
Call Trace:
kobject: 'tx-0': free name
context_switch kernel/sched/core.c:2807 [inline]
__schedule+0x7b8/0x1cd0 kernel/sched/core.c:3383
kobject: 'queues' (ffff8881f59c1448): kobject_cleanup, parent
(null)
kobject: 'queues' (ffff8881f59c1448): calling ktype release
schedule+0x92/0x1c0 kernel/sched/core.c:3427
kobject: 'queues' (ffff8881f59c1448): kset_release
schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3485
kobject: 'queues': free name
__mutex_lock_common kernel/locking/mutex.c:833 [inline]
__mutex_lock+0x73c/0x1470 kernel/locking/mutex.c:893
kobject: 'bridge2160' (ffff8881fff3d470): kobject_uevent_env
kobject: 'bridge2160' (ffff8881fff3d470): kobject_uevent_env:
uevent_suppress caused the event to drop!
kobject: 'batman_adv' (ffff88803a410f00): kobject_uevent_env
kobject: 'batman_adv' (ffff88803a410f00): kobject_uevent_env: filter
function caused the event to drop!
kobject: 'batman_adv' (ffff88803a410f00): kobject_cleanup, parent
(null)
mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908
kobject: 'batman_adv' (ffff88803a410f00): calling ktype release
kobject: (ffff88803a410f00): dynamic_kobj_release
rtnl_lock net/core/rtnetlink.c:72 [inline]
rtnetlink_rcv_msg+0x33a/0xb70 net/core/rtnetlink.c:4280
kobject: 'batman_adv': free name
netlink_rcv_skb+0x14f/0x3c0 net/netlink/af_netlink.c:2432
rtnetlink_rcv+0x1d/0x30 net/core/rtnetlink.c:4297
netlink_unicast_kernel net/netlink/af_netlink.c:1286 [inline]
netlink_unicast+0x45d/0x640 net/netlink/af_netlink.c:1312
netlink_sendmsg+0x7c4/0xc60 net/netlink/af_netlink.c:1877
sock_sendmsg_nosec net/socket.c:646 [inline]
sock_sendmsg+0xce/0x110 net/socket.c:656
SYSC_sendto+0x206/0x310 net/socket.c:1763
SyS_sendto+0x40/0x50 net/socket.c:1731
do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292
entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x413c33
RSP: 002b:00007fff2629ab78 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000413c33
RDX: 0000000000000028 RSI: 0000000000a71df0 RDI: 0000000000000003
RBP: 00007fff2629abe0 R08: 00007fff2629ab80 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003
R13: 00007fff2629aee8 R14: 0000000000000000 R15: 0000000000000000

Showing all locks held in the system:
3 locks held by kworker/1:1/23:
#0: ("%s"("ipv6_addrconf")){+.+.}, at: [<ffffffff813cf8ee>] work_static
include/linux/workqueue.h:199 [inline]
#0: ("%s"("ipv6_addrconf")){+.+.}, at: [<ffffffff813cf8ee>] set_work_data
kernel/workqueue.c:619 [inline]
#0: ("%s"("ipv6_addrconf")){+.+.}, at: [<ffffffff813cf8ee>]
set_work_pool_and_clear_pending kernel/workqueue.c:646 [inline]
#0: ("%s"("ipv6_addrconf")){+.+.}, at: [<ffffffff813cf8ee>]
process_one_work+0x76e/0x1600 kernel/workqueue.c:2085
#1: ((addr_chk_work).work){+.+.}, at: [<ffffffff813cf92b>]
process_one_work+0x7ab/0x1600 kernel/workqueue.c:2089
#2: (rtnl_mutex){+.+.}, at: [<ffffffff84d879e7>] rtnl_lock+0x17/0x20
net/core/rtnetlink.c:72
1 lock held by khungtaskd/1016:
#0: (tasklist_lock){.+.+}, at: [<ffffffff814875a8>]
debug_show_all_locks+0x7f/0x21f kernel/locking/lockdep.c:4544
1 lock held by rsyslogd/6660:
kobject: 'rx-0' (ffff8881f5082f10): kobject_cleanup, parent ffff8881fa3a2948
#0: (&f->f_pos_lock){+.+.}, at: [<ffffffff8194539b>]
__fdget_pos+0xab/0xd0 fs/file.c:769
2 locks held by getty/6782:
#0: (&tty->ldisc_sem){++++}, at: [<ffffffff861c2fb3>]
ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376
#1: (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff8310f4b6>]
n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156
2 locks held by getty/6783:
#0: (&tty->ldisc_sem){++++}, at: [<ffffffff861c2fb3>]
ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376
#1:
kobject: 'rx-0' (ffff8881f5082f10): auto cleanup 'remove' event
(
kobject: 'rx-0' (ffff8881f5082f10): kobject_uevent_env
&ldata->atomic_read_lock
kobject: 'rx-0' (ffff8881f5082f10): kobject_uevent_env: uevent_suppress
caused the event to drop!
){+.+.}
kobject: 'rx-0' (ffff8881f5082f10): auto cleanup kobject_del
, at: [<ffffffff8310f4b6>] n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156
2 locks held by getty/6784:
kobject: 'rx-0' (ffff8881f5082f10): calling ktype release
#0: (&tty->ldisc_sem){++++}, at: [<ffffffff861c2fb3>]
ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376
#1:
kobject: 'rx-0': free name
(&ldata->atomic_read_lock){+.+.}, at: [<ffffffff8310f4b6>]
n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156
2 locks held by getty/6785:
#0: (&tty->ldisc_sem){++++}, at: [<ffffffff861c2fb3>]
ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376
#1: (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff8310f4b6>]
n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156
2 locks held by getty/6786:
#0: (&tty->ldisc_sem){++++}, at: [<ffffffff861c2fb3>]
ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376
#1: (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff8310f4b6>]
n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156
2 locks held by getty/6787:
#0: (&tty->ldisc_sem){++++}, at: [<ffffffff861c2fb3>]
ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376
#1: (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff8310f4b6>]
n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156
2 locks held by getty/6788:
#0: (&tty->ldisc_sem){++++}, at: [<ffffffff861c2fb3>]
ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376
#1: (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff8310f4b6>]
n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156
3 locks held by kworker/1:0/31283:
#0: ("events"){+.+.}, at: [<ffffffff813cf8ee>] work_static
include/linux/workqueue.h:199 [inline]
#0: ("events"){+.+.}, at: [<ffffffff813cf8ee>] set_work_data
kernel/workqueue.c:619 [inline]
#0: ("events"){+.+.}, at: [<ffffffff813cf8ee>]
set_work_pool_and_clear_pending kernel/workqueue.c:646 [inline]
#0: ("events"){+.+.}, at: [<ffffffff813cf8ee>]
process_one_work+0x76e/0x1600 kernel/workqueue.c:2085
#1: ((linkwatch_work).work){+.+.}, at: [<ffffffff813cf92b>]
process_one_work+0x7ab/0x1600 kernel/workqueue.c:2089
#2: (rtnl_mutex){+.+.}, at: [<ffffffff84d879e7>] rtnl_lock+0x17/0x20
net/core/rtnetlink.c:72
3 locks held by kworker/1:2/21571:
#0: ("events"){+.+.}, at: [<ffffffff813cf8ee>] work_static
include/linux/workqueue.h:199 [inline]
#0: ("events"){+.+.}, at: [<ffffffff813cf8ee>] set_work_data
kernel/workqueue.c:619 [inline]
#0: ("events"){+.+.}, at: [<ffffffff813cf8ee>]
set_work_pool_and_clear_pending kernel/workqueue.c:646 [inline]
#0: ("events"){+.+.}, at: [<ffffffff813cf8ee>]
process_one_work+0x76e/0x1600 kernel/workqueue.c:2085
#1: (deferred_process_work){+.+.}, at: [<ffffffff813cf92b>]
process_one_work+0x7ab/0x1600 kernel/workqueue.c:2089
#2: (rtnl_mutex){+.+.}, at: [<ffffffff84d879e7>] rtnl_lock+0x17/0x20
net/core/rtnetlink.c:72
1 lock held by syz-executor.4/25978:
#0:
kobject: 'tx-0' (ffff888039684ad8): kobject_cleanup, parent ffff8881fa3a2948
(rtnl_mutex){+.+.}, at: [<ffffffff84d9103a>] rtnl_lock
net/core/rtnetlink.c:72 [inline]
(rtnl_mutex){+.+.}, at: [<ffffffff84d9103a>] rtnetlink_rcv_msg+0x33a/0xb70
net/core/rtnetlink.c:4280

kobject: 'tx-0' (ffff888039684ad8): auto cleanup 'remove' event
=============================================

NMI backtrace for cpu 0
kobject: 'tx-0' (ffff888039684ad8): kobject_uevent_env
CPU: 0 PID: 1016 Comm: khungtaskd Not tainted 4.14.150 #0
kobject: 'tx-0' (ffff888039684ad8): kobject_uevent_env: uevent_suppress
caused the event to drop!
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:17 [inline]
dump_stack+0x138/0x197 lib/dump_stack.c:53
nmi_cpu_backtrace.cold+0x57/0x94 lib/nmi_backtrace.c:101
nmi_trigger_cpumask_backtrace+0x141/0x189 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:140 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:195 [inline]
watchdog+0x5e7/0xb90 kernel/hung_task.c:274
kthread+0x319/0x430 kernel/kthread.c:232
ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 17662 Comm: kworker/u4:4 Not tainted 4.14.150 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
Workqueue: netns cleanup_net
task: ffff8881a22865c0 task.stack: ffff88819d588000
RIP: 0010:queued_spin_lock include/asm-generic/qspinlock.h:88 [inline]
RIP: 0010:do_raw_spin_lock+0xc8/0x230 kernel/locking/spinlock_debug.c:113
RSP: 0018:ffff8880aef07cd0 EFLAGS: 00000046
RAX: 0000000000000000 RBX: 000000000006be00 RCX: 00000000425b018d
RDX: 0000000000000001 RSI: ffff8881a2286ee0 RDI: ffffffff892c27ac
RBP: ffff8880aef07cf8 R08: 000000000000141d R09: ffffffff88c8b5a8
R10: ffff8881a2286ee0 R11: ffff8881a22865c0 R12: ffffffff892c27a8
R13: ffffffff892c27b0 R14: ffffffff892c27b8 R15: ffffffff892c27a8
FS: 0000000000000000(0000) GS:ffff8880aef00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000001054280 CR3: 00000000a8ffe000 CR4: 00000000001426e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<IRQ>
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:117 [inline]
_raw_spin_lock_irqsave+0x9d/0xcd kernel/locking/spinlock.c:160
debug_object_active_state lib/debugobjects.c:687 [inline]
debug_object_active_state+0xec/0x370 lib/debugobjects.c:675
debug_rcu_head_unqueue kernel/rcu/rcu.h:161 [inline]
rcu_do_batch kernel/rcu/tree.c:2698 [inline]
invoke_rcu_callbacks kernel/rcu/tree.c:2962 [inline]
__rcu_process_callbacks kernel/rcu/tree.c:2929 [inline]
rcu_process_callbacks+0x872/0x12b0 kernel/rcu/tree.c:2946
__do_softirq+0x244/0x9a0 kernel/softirq.c:288
invoke_softirq kernel/softirq.c:368 [inline]
irq_exit+0x160/0x1b0 kernel/softirq.c:409
exiting_irq arch/x86/include/asm/apic.h:648 [inline]
smp_apic_timer_interrupt+0x146/0x5e0 arch/x86/kernel/apic/apic.c:1102
apic_timer_interrupt+0x96/0xa0 arch/x86/entry/entry_64.S:792
</IRQ>
RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:779
[inline]
RIP: 0010:console_trylock_spinning kernel/printk/printk.c:1679 [inline]
RIP: 0010:vprintk_emit kernel/printk/printk.c:1916 [inline]
RIP: 0010:vprintk_emit+0x524/0x600 kernel/printk/printk.c:1882
RSP: 0018:ffff88819d58f778 EFLAGS: 00000297 ORIG_RAX: ffffffffffffff10
RAX: ffff8881a22865c0 RBX: 1ffffffff0ee2a81 RCX: 1ffff11034450ddb
RDX: 0000000000000000 RSI: ffff8881a2286eb8 RDI: 0000000000000297
RBP: ffff88819d58f7b8 R08: ffff8881a22865c0 R09: ffff8881a2286ed8
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000061
R13: 0000000000000297 R14: ffff8880a86006c0 R15: 0000000000000000
vprintk_default+0x28/0x30 kernel/printk/printk.c:1957
vprintk_func+0x5d/0x159 kernel/printk/printk_safe.c:401
printk+0x9e/0xbc kernel/printk/printk.c:1990
kobject_uevent_env+0x1df/0xc23 lib/kobject_uevent.c:370
kobject_uevent+0x20/0x26 lib/kobject_uevent.c:553
kobject_cleanup lib/kobject.c:633 [inline]
kobject_release lib/kobject.c:675 [inline]
kref_put include/linux/kref.h:70 [inline]
kobject_put.cold+0x168/0x2f9 lib/kobject.c:692
netdev_queue_update_kobjects+0x1fa/0x360 net/core/net-sysfs.c:1370
remove_queue_kobjects net/core/net-sysfs.c:1423 [inline]
netdev_unregister_kobject+0x148/0x1d0 net/core/net-sysfs.c:1561
rollback_registered_many+0x694/0xb60 net/core/dev.c:7237
unregister_netdevice_many.part.0+0x1b/0x1e0 net/core/dev.c:8267
unregister_netdevice_many net/core/dev.c:8266 [inline]
default_device_exit_batch+0x31e/0x3d0 net/core/dev.c:8728
ops_exit_list.isra.0+0xfc/0x150 net/core/net_namespace.c:145
cleanup_net+0x3ba/0x880 net/core/net_namespace.c:484
process_one_work+0x863/0x1600 kernel/workqueue.c:2114
worker_thread+0x5d9/0x1050 kernel/workqueue.c:2248
kthread+0x319/0x430 kernel/kthread.c:232
ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404
Code: 84 c0 74 08 3c 03 0f 8e 30 01 00 00 65 8b 05 d0 72 b8 7e 41 39 44 24
08 0f 84 81 00 00 00 31 c0 ba 01 00 00 00 f0 41 0f b1 14 24 <85> c0 0f 85
8d 00 00 00 65 8b 1d a9 72 b8 7e 48 b8 00 00 00 00


---
This bug is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzk...@googlegroups.com.

syzbot will keep track of this bug report. See:
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[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: c3038e71 Linux 4.19.80
git tree: linux-4.19.y
console output: https://syzkaller.appspot.com/x/log.txt?x=16d75a70e00000
kernel config: https://syzkaller.appspot.com/x/.config?x=44c623b7e5432cee
dashboard link: https://syzkaller.appspot.com/bug?extid=2181adf014b148d9b623

compiler: gcc (GCC) 9.0.0 20181231 (experimental)

Unfortunately, I don't have any reproducer for this crash yet.

IMPORTANT: if you fix the bug, please add the following tag to the commit:

Reported-by: syzbot+2181ad...@syzkaller.appspotmail.com

protocol 88fb is buggy, dev hsr_slave_1
protocol 88fb is buggy, dev hsr_slave_0
protocol 88fb is buggy, dev hsr_slave_1
protocol 88fb is buggy, dev hsr_slave_0
protocol 88fb is buggy, dev hsr_slave_1
INFO: task kworker/1:1:24112 blocked for more than 140 seconds.
kobject: 'rx-0' (000000005ca88887): kobject_cleanup, parent 000000000719b8df
Not tainted 4.19.80 #0

"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.

kobject: 'rx-0' (000000005ca88887): auto cleanup 'remove' event
kworker/1:1 D26560 24112 2 0x80000000
kobject: 'rx-0' (000000005ca88887): kobject_uevent_env
Workqueue: events linkwatch_event
kobject: 'rx-0' (000000005ca88887): kobject_uevent_env: uevent_suppress

caused the event to drop!

Call Trace:
context_switch kernel/sched/core.c:2826 [inline]
__schedule+0x866/0x1dc0 kernel/sched/core.c:3515
kobject: 'rx-0' (000000005ca88887): auto cleanup kobject_del
kobject: 'rx-0' (000000005ca88887): calling ktype release
kobject: 'rx-0': free name
kobject: 'tx-0' (000000001ac0d2f2): kobject_cleanup, parent 000000000719b8df
kobject: 'tx-0' (000000001ac0d2f2): auto cleanup 'remove' event
kobject: 'tx-0' (000000001ac0d2f2): kobject_uevent_env
schedule+0x92/0x1c0 kernel/sched/core.c:3559
kobject: 'tx-0' (000000001ac0d2f2): kobject_uevent_env: uevent_suppress

caused the event to drop!

kobject: 'tx-0' (000000001ac0d2f2): auto cleanup kobject_del
kobject: 'tx-0' (000000001ac0d2f2): calling ktype release
schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3617
kobject: 'tx-0': free name
__mutex_lock_common kernel/locking/mutex.c:1002 [inline]
__mutex_lock+0x726/0x1300 kernel/locking/mutex.c:1072
kobject: 'queues' (000000000719b8df): kobject_cleanup, parent
(null)
kobject: 'queues' (000000000719b8df): calling ktype release
kobject: 'queues' (000000000719b8df): kset_release
kobject: 'queues': free name
kobject: 'bridge62' (00000000a5beb1fc): kobject_uevent_env
kobject: 'bridge62' (00000000a5beb1fc): kobject_uevent_env: uevent_suppress

caused the event to drop!

kobject: 'batman_adv' (000000001a6128eb): kobject_uevent_env
kobject: 'batman_adv' (000000001a6128eb): kobject_uevent_env: filter

function caused the event to drop!

kobject: 'batman_adv' (000000001a6128eb): kobject_cleanup, parent
(null)
kobject: 'batman_adv' (000000001a6128eb): calling ktype release
kobject: (000000001a6128eb): dynamic_kobj_release
kobject: 'batman_adv': free name
mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087
rtnl_lock+0x17/0x20 net/core/rtnetlink.c:77
linkwatch_event+0xf/0x70 net/core/link_watch.c:236
process_one_work+0x989/0x1750 kernel/workqueue.c:2153
worker_thread+0x98/0xe40 kernel/workqueue.c:2296
kthread+0x354/0x420 kernel/kthread.c:246
ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415
INFO: task kworker/0:1:9445 blocked for more than 140 seconds.
Not tainted 4.19.80 #0

"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.

kworker/0:1 D26560 9445 2 0x80000000
Workqueue: events switchdev_deferred_process_work
Call Trace:
context_switch kernel/sched/core.c:2826 [inline]
__schedule+0x866/0x1dc0 kernel/sched/core.c:3515
schedule+0x92/0x1c0 kernel/sched/core.c:3559
schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3617
__mutex_lock_common kernel/locking/mutex.c:1002 [inline]
__mutex_lock+0x726/0x1300 kernel/locking/mutex.c:1072
mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087
rtnl_lock+0x17/0x20 net/core/rtnetlink.c:77
switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:150
process_one_work+0x989/0x1750 kernel/workqueue.c:2153
worker_thread+0x98/0xe40 kernel/workqueue.c:2296
kthread+0x354/0x420 kernel/kthread.c:246
ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415
INFO: task syz-executor.2:17175 blocked for more than 140 seconds.
kobject: 'rx-0' (00000000a37f90bb): kobject_cleanup, parent 000000007474d607
Not tainted 4.19.80 #0

"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.

kobject: 'rx-0' (00000000a37f90bb): auto cleanup 'remove' event
syz-executor.2 D28984 17175 15933 0x00000004
Call Trace:
kobject: 'rx-0' (00000000a37f90bb): kobject_uevent_env
context_switch kernel/sched/core.c:2826 [inline]
__schedule+0x866/0x1dc0 kernel/sched/core.c:3515
kobject: 'rx-0' (00000000a37f90bb): kobject_uevent_env: uevent_suppress

caused the event to drop!

kobject: 'rx-0' (00000000a37f90bb): auto cleanup kobject_del
kobject: 'rx-0' (00000000a37f90bb): calling ktype release
schedule+0x92/0x1c0 kernel/sched/core.c:3559
kobject: 'rx-0': free name
schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3617
kobject: 'tx-0' (0000000064987e61): kobject_cleanup, parent 000000007474d607
__mutex_lock_common kernel/locking/mutex.c:1002 [inline]
__mutex_lock+0x726/0x1300 kernel/locking/mutex.c:1072
kobject: 'tx-0' (0000000064987e61): auto cleanup 'remove' event
kobject: 'tx-0' (0000000064987e61): kobject_uevent_env
kobject: 'tx-0' (0000000064987e61): kobject_uevent_env: uevent_suppress

caused the event to drop!

kobject: 'tx-0' (0000000064987e61): auto cleanup kobject_del
mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087
kobject: 'tx-0' (0000000064987e61): calling ktype release
kobject: 'tx-0': free name
kobject: 'queues' (000000007474d607): kobject_cleanup, parent
(null)
rtnl_lock+0x17/0x20 net/core/rtnetlink.c:77
kobject: 'queues' (000000007474d607): calling ktype release
sock_do_ioctl+0x24e/0x2f0 net/socket.c:963
kobject: 'queues' (000000007474d607): kset_release
kobject: 'queues': free name
kobject: 'bridge61' (00000000e7b9d189): kobject_uevent_env
kobject: 'bridge61' (00000000e7b9d189): kobject_uevent_env: uevent_suppress

caused the event to drop!

sock_ioctl+0x325/0x610 net/socket.c:1074
kobject: 'batman_adv' (00000000fbaea216): kobject_uevent_env
kobject: 'batman_adv' (00000000fbaea216): kobject_uevent_env: filter

function caused the event to drop!

kobject: 'batman_adv' (00000000fbaea216): kobject_cleanup, parent
(null)
kobject: 'batman_adv' (00000000fbaea216): calling ktype release
kobject: (00000000fbaea216): dynamic_kobj_release
vfs_ioctl fs/ioctl.c:46 [inline]
file_ioctl fs/ioctl.c:501 [inline]
do_vfs_ioctl+0xd5f/0x1380 fs/ioctl.c:688
kobject: 'batman_adv': free name
ksys_ioctl+0xab/0xd0 fs/ioctl.c:705
__do_sys_ioctl fs/ioctl.c:712 [inline]
__se_sys_ioctl fs/ioctl.c:710 [inline]
__x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:710
do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x459f39
Code: c6 10 0f 11 07 48 83 c7 10 0f 10 06 48 83 c6 10 0f 11 07 48 83 c7 10
0f 10 06 48 83 c6 10 0f 11 07 48 83 c7 10 0f 10 06 48 83 <c6> 10 0f 11 07
48 83 c7 10 0f 10 06 48 83 c6 10 0f 11 07 48 83 c7
RSP: 002b:00007f697e1d1c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459f39
RDX: 0000000000400200 RSI: 0000000000008912 RDI: 0000000000000003
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f697e1d26d4
R13: 00000000004c3b10 R14: 00000000004d7aa8 R15: 00000000ffffffff
INFO: task syz-executor.1:17173 blocked for more than 140 seconds.
Not tainted 4.19.80 #0

"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.

syz-executor.1 D28456 17173 15936 0x00000004
Call Trace:
context_switch kernel/sched/core.c:2826 [inline]
__schedule+0x866/0x1dc0 kernel/sched/core.c:3515
schedule+0x92/0x1c0 kernel/sched/core.c:3559
schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3617
__mutex_lock_common kernel/locking/mutex.c:1002 [inline]
__mutex_lock+0x726/0x1300 kernel/locking/mutex.c:1072
mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087
rtnl_lock net/core/rtnetlink.c:77 [inline]
rtnetlink_rcv_msg+0x40a/0xb00 net/core/rtnetlink.c:4744
netlink_rcv_skb+0x17d/0x460 net/netlink/af_netlink.c:2454
rtnetlink_rcv+0x1d/0x30 net/core/rtnetlink.c:4765
netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline]
netlink_unicast+0x537/0x720 net/netlink/af_netlink.c:1343
netlink_sendmsg+0x8ae/0xd70 net/netlink/af_netlink.c:1908
sock_sendmsg_nosec net/socket.c:622 [inline]
sock_sendmsg+0xd7/0x130 net/socket.c:632
___sys_sendmsg+0x803/0x920 net/socket.c:2115
__sys_sendmsg+0x105/0x1d0 net/socket.c:2153
__do_sys_sendmsg net/socket.c:2162 [inline]
__se_sys_sendmsg net/socket.c:2160 [inline]
__x64_sys_sendmsg+0x78/0xb0 net/socket.c:2160
do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x459f39
Code: c6 10 0f 11 07 48 83 c7 10 0f 10 06 48 83 c6 10 0f 11 07 48 83 c7 10
0f 10 06 48 83 c6 10 0f 11 07 48 83 c7 10 0f 10 06 48 83 <c6> 10 0f 11 07
48 83 c7 10 0f 10 06 48 83 c6 10 0f 11 07 48 83 c7
RSP: 002b:00007fb41b36ac78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459f39
RDX: 0000000010000000 RSI: 0000000020000240 RDI: 0000000000000003
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fb41b36b6d4
R13: 00000000004c8320 R14: 00000000004de420 R15: 00000000ffffffff
INFO: task syz-executor.4:17180 blocked for more than 140 seconds.
kobject: 'rx-0' (00000000e5d7320c): kobject_cleanup, parent 0000000078ea8ba8
Not tainted 4.19.80 #0

"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.

kobject: 'rx-0' (00000000e5d7320c): auto cleanup 'remove' event
syz-executor.4 D29464 17180 15875 0x00000004
kobject: 'rx-0' (00000000e5d7320c): kobject_uevent_env
Call Trace:
context_switch kernel/sched/core.c:2826 [inline]
__schedule+0x866/0x1dc0 kernel/sched/core.c:3515
schedule+0x92/0x1c0 kernel/sched/core.c:3559
kobject: 'rx-0' (00000000e5d7320c): kobject_uevent_env: uevent_suppress

caused the event to drop!

schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3617
__mutex_lock_common kernel/locking/mutex.c:1002 [inline]
__mutex_lock+0x726/0x1300 kernel/locking/mutex.c:1072
mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087
kobject: 'rx-0' (00000000e5d7320c): auto cleanup kobject_del
rtnl_lock+0x17/0x20 net/core/rtnetlink.c:77
sock_do_ioctl+0x24e/0x2f0 net/socket.c:963
sock_ioctl+0x325/0x610 net/socket.c:1074
vfs_ioctl fs/ioctl.c:46 [inline]
file_ioctl fs/ioctl.c:501 [inline]
do_vfs_ioctl+0xd5f/0x1380 fs/ioctl.c:688
kobject: 'rx-0' (00000000e5d7320c): calling ktype release
kobject: 'rx-0': free name
kobject: 'tx-0' (00000000786a3356): kobject_cleanup, parent 0000000078ea8ba8
kobject: 'tx-0' (00000000786a3356): auto cleanup 'remove' event
kobject: 'tx-0' (00000000786a3356): kobject_uevent_env
ksys_ioctl+0xab/0xd0 fs/ioctl.c:705
__do_sys_ioctl fs/ioctl.c:712 [inline]
__se_sys_ioctl fs/ioctl.c:710 [inline]
__x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:710
do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293
entry_SYSCALL_64_after_hwframe+0x49/0xbe
kobject: 'tx-0' (00000000786a3356): kobject_uevent_env: uevent_suppress

caused the event to drop!

RIP: 0033:0x459f39
kobject: 'tx-0' (00000000786a3356): auto cleanup kobject_del
Code: Bad RIP value.
RSP: 002b:00007f8b2d9aec78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459f39
RDX: 0000000020000000 RSI: 0000001000008912 RDI: 0000000000000003
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f8b2d9af6d4
R13: 00000000004c1521 R14: 00000000004d4dc0 R15: 00000000ffffffff
INFO: task syz-executor.4:17185 blocked for more than 140 seconds.
kobject: 'tx-0' (00000000786a3356): calling ktype release
Not tainted 4.19.80 #0
kobject: 'tx-0': free name

"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.

kobject: 'queues' (0000000078ea8ba8): kobject_cleanup, parent
(null)
syz-executor.4 D
kobject: 'queues' (0000000078ea8ba8): calling ktype release
29352 17185 15875 0x00000004
kobject: 'queues' (0000000078ea8ba8): kset_release
Call Trace:
context_switch kernel/sched/core.c:2826 [inline]
__schedule+0x866/0x1dc0 kernel/sched/core.c:3515
kobject: 'queues': free name
kobject: 'bridge60' (00000000c5c3dc0f): kobject_uevent_env
kobject: 'bridge60' (00000000c5c3dc0f): kobject_uevent_env: uevent_suppress

caused the event to drop!

kobject: 'batman_adv' (000000007120ddfb): kobject_uevent_env
schedule+0x92/0x1c0 kernel/sched/core.c:3559
schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3617
__mutex_lock_common kernel/locking/mutex.c:1002 [inline]
__mutex_lock+0x726/0x1300 kernel/locking/mutex.c:1072
kobject: 'batman_adv' (000000007120ddfb): kobject_uevent_env: filter

function caused the event to drop!

kobject: 'batman_adv' (000000007120ddfb): kobject_cleanup, parent
(null)
mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087
kobject: 'batman_adv' (000000007120ddfb): calling ktype release
kobject: (000000007120ddfb): dynamic_kobj_release
rtnl_lock+0x17/0x20 net/core/rtnetlink.c:77
kobject: 'batman_adv': free name
sock_do_ioctl+0x24e/0x2f0 net/socket.c:963
sock_ioctl+0x325/0x610 net/socket.c:1074
vfs_ioctl fs/ioctl.c:46 [inline]
file_ioctl fs/ioctl.c:501 [inline]
do_vfs_ioctl+0xd5f/0x1380 fs/ioctl.c:688
ksys_ioctl+0xab/0xd0 fs/ioctl.c:705
__do_sys_ioctl fs/ioctl.c:712 [inline]
__se_sys_ioctl fs/ioctl.c:710 [inline]
__x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:710
do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x459f39
Code: Bad RIP value.
RSP: 002b:00007f8b2d98dc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459f39
RDX: 0000000020000000 RSI: 0000001000008912 RDI: 0000000000000003
RBP: 000000000075bfc8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f8b2d98e6d4
R13: 00000000004c1521 R14: 00000000004d4dc0 R15: 00000000ffffffff
INFO: task syz-executor.0:17423 blocked for more than 140 seconds.
Not tainted 4.19.80 #0

"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.

syz-executor.0 D29096 17423 30285 0x00000004
Call Trace:
context_switch kernel/sched/core.c:2826 [inline]
__schedule+0x866/0x1dc0 kernel/sched/core.c:3515
schedule+0x92/0x1c0 kernel/sched/core.c:3559
schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3617
__mutex_lock_common kernel/locking/mutex.c:1002 [inline]
__mutex_lock+0x726/0x1300 kernel/locking/mutex.c:1072
mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087
rtnl_lock+0x17/0x20 net/core/rtnetlink.c:77
sock_do_ioctl+0x24e/0x2f0 net/socket.c:963
sock_ioctl+0x325/0x610 net/socket.c:1074
vfs_ioctl fs/ioctl.c:46 [inline]
file_ioctl fs/ioctl.c:501 [inline]
do_vfs_ioctl+0xd5f/0x1380 fs/ioctl.c:688
net_ratelimit: 18 callbacks suppressed
protocol 88fb is buggy, dev hsr_slave_0
protocol 88fb is buggy, dev hsr_slave_1
ksys_ioctl+0xab/0xd0 fs/ioctl.c:705
__do_sys_ioctl fs/ioctl.c:712 [inline]
__se_sys_ioctl fs/ioctl.c:710 [inline]
__x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:710
do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x459f39
Code: Bad RIP value.
RSP: 002b:00007fbf1a35ec78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459f39
RDX: 0000000000400200 RSI: 0000000000008912 RDI: 0000000000000007
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fbf1a35f6d4
R13: 00000000004c3b10 R14: 00000000004d7aa8 R15: 00000000ffffffff

Showing all locks held in the system:

kobject: 'rx-0' (00000000037136a0): kobject_cleanup, parent 000000004ed4ece7
1 lock held by khungtaskd/1037:
#0: 000000007eabaabd (rcu_read_lock){....}, at:
debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:4438
kobject: 'rx-0' (00000000037136a0): auto cleanup 'remove' event
3 locks held by kworker/1:2/2724:
#0: 000000005c152732 ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at:
__write_once_size include/linux/compiler.h:220 [inline]
#0: 000000005c152732 ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at:
arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
#0: 000000005c152732 ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at:
atomic64_set include/asm-generic/atomic-instrumented.h:40 [inline]
#0: 000000005c152732 ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at:
atomic_long_set include/asm-generic/atomic-long.h:59 [inline]
#0: 000000005c152732 ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at:
set_work_data kernel/workqueue.c:617 [inline]
#0: 000000005c152732 ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at:
set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline]
#0: 000000005c152732 ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at:
process_one_work+0x87e/0x1750 kernel/workqueue.c:2124
kobject: 'rx-0' (00000000037136a0): kobject_uevent_env
#1: 00000000f6b39ce8 ((addr_chk_work).work){+.+.}, at:
process_one_work+0x8b4/0x1750 kernel/workqueue.c:2128
#2: 00000000b510b03a (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20
net/core/rtnetlink.c:77
3 locks held by rs:main Q:Reg/7343:
kobject: 'rx-0' (00000000037136a0): kobject_uevent_env: uevent_suppress

caused the event to drop!

#0: 00000000aeb6dab0 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110
fs/file.c:767
#1: 000000009a5eea3e (sb_writers#4){.+.+}, at: file_start_write
include/linux/fs.h:2775 [inline]
#1: 000000009a5eea3e (sb_writers#4){.+.+}, at: vfs_write+0x429/0x560
fs/read_write.c:548
#2: 00000000029c74e8 (&rq->lock){-.-.}, at: rq_lock
kernel/sched/sched.h:1821 [inline]
#2: 00000000029c74e8 (&rq->lock){-.-.}, at: __schedule+0x1f8/0x1dc0
kernel/sched/core.c:3453
1 lock held by rsyslogd/7345:
2 locks held by getty/7467:
#0: 00000000d519d37e (&tty->ldisc_sem){++++}, at:
ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362
#1: 00000000ae994196 (&ldata->atomic_read_lock
kobject: 'rx-0' (00000000037136a0): auto cleanup kobject_del
){+.+.}
kobject: 'rx-0' (00000000037136a0): calling ktype release
, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154
2 locks held by getty/7468:
kobject: 'rx-0': free name
#0: 00000000384e28c4 (&tty->ldisc_sem){++++}, at:
ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362
#1: 000000007a377459 (
kobject: 'tx-0' (000000001e17f832): kobject_cleanup, parent 000000004ed4ece7
&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30
drivers/tty/n_tty.c:2154
2 locks held by getty/7469:
#0: 00000000734b2a33 (&tty->ldisc_sem){++++}, at:
ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362
#1: 00000000f9d1396f (
protocol 88fb is buggy, dev hsr_slave_0
&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30
drivers/tty/n_tty.c:2154
2 locks held by getty/7470:
#0: 00000000a7fdc137 (&tty->ldisc_sem){++++}, at:
ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362
protocol 88fb is buggy, dev hsr_slave_1
#1: 0000000013b34fa4 (&ldata->atomic_read_lock){+.+.}, at:
n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154
2 locks held by getty/7471:
#0: 000000008e693960 (&tty->ldisc_sem){++++}, at:
ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362
#1: 00000000e37ce521 (&ldata->atomic_read_lock){+.+.}, at:
n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154
2 locks held by getty/7472:
#0: 000000005166f954 (&tty->ldisc_sem){++++}, at:
ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362
#1: 00000000415da0e5 (&ldata->atomic_read_lock){+.+.}, at:
n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154
2 locks held by getty/7473:
#0:
kobject: 'tx-0' (000000001e17f832): auto cleanup 'remove' event
0000000048d43469
kobject: 'tx-0' (000000001e17f832): kobject_uevent_env
(&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40
drivers/tty/tty_ldsem.c:362
#1: 0000000078a60be1 (&ldata->atomic_read_lock){+.+.}, at:
n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154
3 locks held by kworker/1:1/24112:
#0: 00000000a00ccba4 ((wq_completion)"events"
kobject: 'tx-0' (000000001e17f832): kobject_uevent_env: uevent_suppress

caused the event to drop!

){+.+.}, at: __write_once_size include/linux/compiler.h:220 [inline]
){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34
[inline]
){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:40
[inline]
){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:59 [inline]
){+.+.}, at: set_work_data kernel/workqueue.c:617 [inline]
){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline]
){+.+.}, at: process_one_work+0x87e/0x1750 kernel/workqueue.c:2124
#1: 00000000b0addc7a ((linkwatch_work).work){+.+.}, at:
process_one_work+0x8b4/0x1750 kernel/workqueue.c:2128
#2: 00000000b510b03a (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20
net/core/rtnetlink.c:77
kobject: 'tx-0' (000000001e17f832): auto cleanup kobject_del
3 locks held by kworker/0:1/9445:
#0: 00000000a00ccba4 ((wq_completion)"events"){+.+.}, at:
__write_once_size include/linux/compiler.h:220 [inline]
#0: 00000000a00ccba4 ((wq_completion)"events"){+.+.}, at:
arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
#0: 00000000a00ccba4 ((wq_completion)"events"){+.+.}, at: atomic64_set
include/asm-generic/atomic-instrumented.h:40 [inline]
#0: 00000000a00ccba4 ((wq_completion)"events"){+.+.}, at: atomic_long_set
include/asm-generic/atomic-long.h:59 [inline]
#0: 00000000a00ccba4 ((wq_completion)"events"){+.+.}, at: set_work_data
kernel/workqueue.c:617 [inline]
#0: 00000000a00ccba4 ((wq_completion)"events"){+.+.}, at:
set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline]
#0: 00000000a00ccba4 ((wq_completion)"events"){+.+.}, at:
process_one_work+0x87e/0x1750 kernel/workqueue.c:2124
#1: 000000005b35cd0d (deferred_process_work){+.+.}, at:
process_one_work+0x8b4/0x1750 kernel/workqueue.c:2128
#2: 00000000b510b03a (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20
net/core/rtnetlink.c:77
7 locks held by kworker/u4:1/27624:
1 lock held by syz-executor.2/17175:
#0: 00000000b510b03a (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20
net/core/rtnetlink.c:77
1 lock held by syz-executor.1/17173:
#0: 00000000b510b03a (
kobject: 'tx-0' (000000001e17f832): calling ktype release
rtnl_mutex){+.+.}, at: rtnl_lock net/core/rtnetlink.c:77 [inline]
rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x40a/0xb00
net/core/rtnetlink.c:4744
1 lock held by syz-executor.4/17180:
#0: 00000000b510b03a (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20
net/core/rtnetlink.c:77
1 lock held by syz-executor.4/17185:
#0: 00000000b510b03a (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20
net/core/rtnetlink.c:77
1 lock held by syz-executor.0/17423:
#0: 00000000b510b03a (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20
net/core/rtnetlink.c:77

kobject: 'tx-0': free name
=============================================

NMI backtrace for cpu 1
CPU: 1 PID: 1037 Comm: khungtaskd Not tainted 4.19.80 #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+0x172/0x1f0 lib/dump_stack.c:113
nmi_cpu_backtrace.cold+0x63/0xa4 lib/nmi_backtrace.c:101
nmi_trigger_cpumask_backtrace+0x1b0/0x1f8 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:203 [inline]
watchdog+0x9df/0xee0 kernel/hung_task.c:287
kthread+0x354/0x420 kernel/kthread.c:246
kobject: 'queues' (000000004ed4ece7): kobject_cleanup, parent
(null)
ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415
Sending NMI from CPU 1 to CPUs 0:
kobject: 'queues' (000000004ed4ece7): calling ktype release

NMI backtrace for cpu 0

CPU: 0 PID: 27624 Comm: kworker/u4:1 Not tainted 4.19.80 #0

Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
Workqueue: netns cleanup_net

RIP: 0010:hrtimer_interrupt+0x314/0x770 kernel/time/hrtimer.c:1521
Code: ff ff ff 7f 41 80 4e 44 08 49 89 46 68 e8 94 ee e3 ff e8 af d4 0e 00
4c 89 e6 b9 0f 00 00 00 4c 89 ea 4c 89 f7 e8 7c e0 ff ff <be> ff 00 00 00
4c 89 f7 e8 0f bd ff ff 49 89 c4 48 8b 45 b0 80 38
RSP: 0018:ffff8880ae807f18 EFLAGS: 00000092
RAX: 0000000000000000 RBX: dffffc0000000000 RCX: 1ffff11015d00fd0
RDX: 0000000000010000 RSI: ffffffff815bddea RDI: 0000000000000005
RBP: ffff8880ae807fb0 R08: ffff88805028a240 R09: ffffed1015d04733
R10: ffffed1015d04732 R11: ffff8880ae823993 R12: 000001cd9d875b00
R13: 0000000000000082 R14: ffff8880ae825b80 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000

CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033

CR2: 00007f267000a008 CR3: 0000000093138000 CR4: 00000000001426f0

DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<IRQ>

local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1067 [inline]
smp_apic_timer_interrupt+0x111/0x550 arch/x86/kernel/apic/apic.c:1092
apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:893
</IRQ>
RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:789
[inline]
RIP: 0010:console_trylock_spinning kernel/printk/printk.c:1689 [inline]
RIP: 0010:vprintk_emit+0x5b8/0x690 kernel/printk/printk.c:1926
Code: 48 b8 00 00 00 00 00 fc ff df 41 80 7c 05 00 00 0f 85 a2 00 00 00 48
83 3d cc 2a 1d 07 00 74 29 e8 bd ab 15 00 48 89 df 57 9d <0f> 1f 44 00 00
e9 79 fe ff ff e8 a9 ab 15 00 0f 0b e8 a2 ab 15 00
RSP: 0018:ffff8880152477b8 EFLAGS: 00000293 ORIG_RAX: ffffffffffffff13
RAX: ffff88805028a240 RBX: 0000000000000293 RCX: 1ffff1100a05156b
RDX: 0000000000000000 RSI: ffffffff81551b83 RDI: 0000000000000293
RBP: ffff888015247800 R08: ffff88805028a240 R09: ffff88805028ab58
R10: 0000000000000000 R11: 0000000000000000 R12: 000000000000003b
R13: 1ffffffff10e48c9 R14: 0000000000000200 R15: ffff8880a82765c0
vprintk_default+0x28/0x30 kernel/printk/printk.c:1968
vprintk_func+0x7e/0x189 kernel/printk/printk_safe.c:398
printk+0xba/0xed kernel/printk/printk.c:2001
kobject_cleanup lib/kobject.c:660 [inline]
kobject_release lib/kobject.c:691 [inline]
kref_put include/linux/kref.h:70 [inline]
kobject_put.cold+0x266/0x2e6 lib/kobject.c:708
kset_unregister+0x38/0x50 lib/kobject.c:850
remove_queue_kobjects net/core/net-sysfs.c:1570 [inline]
netdev_unregister_kobject+0x18c/0x1f0 net/core/net-sysfs.c:1718
rollback_registered_many+0x6bb/0xda0 net/core/dev.c:8029
unregister_netdevice_many.part.0+0x1b/0x1f0 net/core/dev.c:9115
unregister_netdevice_many net/core/dev.c:9114 [inline]
default_device_exit_batch+0x34e/0x410 net/core/dev.c:9586
ops_exit_list.isra.0+0xfc/0x150 net/core/net_namespace.c:156
cleanup_net+0x3fb/0x960 net/core/net_namespace.c:552
process_one_work+0x989/0x1750 kernel/workqueue.c:2153
worker_thread+0x98/0xe40 kernel/workqueue.c:2296
kthread+0x354/0x420 kernel/kthread.c:246
ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415

[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.

[syzbot]