INFO: task kworker/1:4:9193 blocked for more than 143 seconds.
      Not tainted 5.12.0-rc8-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/1:4     state:D stack:26016 pid: 9193 ppid:     2 flags:0x00004000
Workqueue: ipv6_addrconf addrconf_verify_work
Call Trace:
 context_switch kernel/sched/core.c:4322 [inline]
 __schedule+0x911/0x21b0 kernel/sched/core.c:5073
 schedule+0xcf/0x270 kernel/sched/core.c:5152
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:5211
 __mutex_lock_common kernel/locking/mutex.c:1026 [inline]
 __mutex_lock+0x81f/0x1120 kernel/locking/mutex.c:1096
 addrconf_verify_work+0xa/0x20 net/ipv6/addrconf.c:4572
 process_one_work+0x98d/0x1600 kernel/workqueue.c:2275
 worker_thread+0x64c/0x1120 kernel/workqueue.c:2421
 kthread+0x3b1/0x4a0 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294
INFO: task kworker/1:7:9572 blocked for more than 144 seconds.
      Not tainted 5.12.0-rc8-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/1:7     state:D stack:27352 pid: 9572 ppid:     2 flags:0x00004000
Workqueue: events linkwatch_event
Call Trace:
 context_switch kernel/sched/core.c:4322 [inline]
 __schedule+0x911/0x21b0 kernel/sched/core.c:5073
 schedule+0xcf/0x270 kernel/sched/core.c:5152
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:5211
 __mutex_lock_common kernel/locking/mutex.c:1026 [inline]
 __mutex_lock+0x81f/0x1120 kernel/locking/mutex.c:1096
 linkwatch_event+0xb/0x60 net/core/link_watch.c:250
 process_one_work+0x98d/0x1600 kernel/workqueue.c:2275
 worker_thread+0x64c/0x1120 kernel/workqueue.c:2421
 kthread+0x3b1/0x4a0 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294

Showing all locks held in the system:
1 lock held by khungtaskd/1629:
 #0: ffffffff8bf74360 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6328
1 lock held by systemd-journal/4818:
1 lock held by in:imklog/8097:
 #0: ffff88801bc2a870 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:974
3 locks held by kworker/1:4/9193:
 #0: ffff888021862138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: ffff888021862138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline]
 #0: ffff888021862138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline]
 #0: ffff888021862138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline]
 #0: ffff888021862138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline]
 #0: ffff888021862138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x871/0x1600 kernel/workqueue.c:2246
 #1: ffffc9000269fda8 ((addr_chk_work).work){+.+.}-{0:0}, at: process_one_work+0x8a5/0x1600 kernel/workqueue.c:2250
 #2: ffffffff8d66bf68 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_verify_work+0xa/0x20 net/ipv6/addrconf.c:4572
3 locks held by kworker/1:7/9572:
 #0: ffff888010464d38 ((wq_completion)events){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: ffff888010464d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline]
 #0: ffff888010464d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline]
 #0: ffff888010464d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline]
 #0: ffff888010464d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline]
 #0: ffff888010464d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x871/0x1600 kernel/workqueue.c:2246
 #1: ffffc90009b37da8 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x8a5/0x1600 kernel/workqueue.c:2250
 #2: ffffffff8d66bf68 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xb/0x60 net/core/link_watch.c:250
1 lock held by syz-executor.1/12891:
2 locks held by syz-executor.5/23327:

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

NMI backtrace for cpu 0
CPU: 0 PID: 1629 Comm: khungtaskd Not tainted 5.12.0-rc8-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:79 [inline]
 dump_stack+0x141/0x1d7 lib/dump_stack.c:120
 nmi_cpu_backtrace.cold+0x44/0xd7 lib/nmi_backtrace.c:105
 nmi_trigger_cpumask_backtrace+0x1b3/0x230 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:209 [inline]
 watchdog+0xd48/0xfb0 kernel/hung_task.c:294
 kthread+0x3b1/0x4a0 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 13184 Comm: syz-executor.3 Not tainted 5.12.0-rc8-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:__sanitizer_cov_trace_pc+0x37/0x60 kernel/kcov.c:197
Code: 81 e1 00 01 00 00 65 48 8b 14 25 00 f0 01 00 a9 00 01 ff 00 74 0e 85 c9 74 35 8b 82 34 15 00 00 85 c0 74 2b 8b 82 10 15 00 00 <83> f8 02 75 20 48 8b 8a 18 15 00 00 8b 92 14 15 00 00 48 8b 01 48
RSP: 0000:ffffc9000b76faf8 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffff88802186b880 RCX: 0000000000000000
RDX: ffff88802186b880 RSI: ffffffff812a534f RDI: ffff88802186cf08
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffff812a5302 R11: 0000000000000000 R12: ffff88802186b880
R13: ffffed100430d9e1 R14: ffff88802186cf08 R15: 00000000f55462c0
FS:  0000000000000000(0000) GS:ffff8880b9d00000(0063) knlGS:00000000f5546b40
CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 0000000000000050 CR3: 000000006dcb1000 CR4: 00000000001506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 local_bh_enable include/linux/bottom_half.h:32 [inline]
 fpregs_unlock arch/x86/include/asm/fpu/api.h:78 [inline]
 copy_fpstate_to_sigframe+0x2cf/0xae0 arch/x86/kernel/fpu/signal.c:196
 get_sigframe.constprop.0+0x305/0x4a0 arch/x86/ia32/ia32_signal.c:223
 ia32_setup_rt_frame+0x98/0xb90 arch/x86/ia32/ia32_signal.c:320
 setup_rt_frame arch/x86/kernel/signal.c:696 [inline]
 handle_signal arch/x86/kernel/signal.c:746 [inline]
 arch_do_signal_or_restart+0xc84/0x1eb0 arch/x86/kernel/signal.c:791
 handle_signal_work kernel/entry/common.c:147 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:171 [inline]
 exit_to_user_mode_prepare+0x148/0x250 kernel/entry/common.c:208
 irqentry_exit_to_user_mode+0x5/0x40 kernel/entry/common.c:314
 exc_page_fault+0xc6/0x180 arch/x86/mm/fault.c:1534
 asm_exc_page_fault+0x1e/0x30 arch/x86/include/asm/idtentry.h:577
RIP: 0023:0x80520b7
Code: 0c 50 e8 ac 5a 01 00 83 c4 10 85 c0 0f 84 b9 01 00 00 65 f0 83 2d d8 ff ff ff 01 8b 5c 24 08 e8 6f f7 00 00 8b 4c 24 0c 8b 00 <8b> 71 50 89 41 54 85 c0 75 05 83 fe ff 74 19 6b 44 24 1c 34 8b 4c
RSP: 002b:00000000f5546640 EFLAGS: 00010283
RAX: 0000000000000002 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000008052094 RSI: 0000000000000004 RDI: 00000000080ea247
RBP: 000000000819afc0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000