Extracting prog: 7m10.461289528s
Minimizing prog: 30m36.590920122s
Simplifying prog options: 11m43.678289687s
Extracting C: 3m13.827953623s
Simplifying C: 0s


extracting reproducer from 1 programs
testing a last program of every proc
single: executing 1 programs separately with timeout 30s
testing program (duration=30s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$inet6-ioctl$sock_SIOCETHTOOL
detailed listing:
executing program 0:
r0 = socket$inet6(0xa, 0x1, 0x0)
ioctl$sock_SIOCETHTOOL(r0, 0x89f0, &(0x7f00000002c0)={'bridge0\x00', &(0x7f0000000340)=@ethtool_regs={0x4, 0x0, 0x1b, "aede62497cf56c9ab5bfd7b842f6b7ea6b8579d27d9c47d7da09f5"}})

program did not crash
program did not crash
single: failed to extract reproducer
single: executing 1 programs separately with timeout 6m0s
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$inet6-ioctl$sock_SIOCETHTOOL
detailed listing:
executing program 0:
r0 = socket$inet6(0xa, 0x1, 0x0)
ioctl$sock_SIOCETHTOOL(r0, 0x89f0, &(0x7f00000002c0)={'bridge0\x00', &(0x7f0000000340)=@ethtool_regs={0x4, 0x0, 0x1b, "aede62497cf56c9ab5bfd7b842f6b7ea6b8579d27d9c47d7da09f5"}})

program crashed: INFO: task hung in reg_process_self_managed_hints
single: successfully extracted reproducer
found reproducer with 2 syscalls
minimizing guilty program
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$inet6
detailed listing:
executing program 0:
socket$inet6(0xa, 0x1, 0x0)

program did not crash
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): ioctl$sock_SIOCETHTOOL
detailed listing:
executing program 0:
ioctl$sock_SIOCETHTOOL(0xffffffffffffffff, 0x89f0, &(0x7f00000002c0)={'bridge0\x00', &(0x7f0000000340)=@ethtool_regs={0x4, 0x0, 0x1b, "aede62497cf56c9ab5bfd7b842f6b7ea6b8579d27d9c47d7da09f5"}})

program did not crash
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$inet6-ioctl$sock_SIOCETHTOOL
detailed listing:
executing program 0:
r0 = socket$inet6(0xa, 0x1, 0x0)
ioctl$sock_SIOCETHTOOL(r0, 0x89f0, 0x0)

program did not crash
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$inet6-ioctl$sock_SIOCETHTOOL
detailed listing:
executing program 0:
r0 = socket$inet6(0xa, 0x1, 0x0)
ioctl$sock_SIOCETHTOOL(r0, 0x89f0, &(0x7f00000002c0)={'bridge0\x00', 0x0})

program did not crash
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$inet6-ioctl$sock_SIOCETHTOOL
detailed listing:
executing program 0:
r0 = socket$inet6(0xa, 0x1, 0x0)
ioctl$sock_SIOCETHTOOL(r0, 0x89f0, &(0x7f00000002c0)={'bridge0\x00', &(0x7f0000000340)=@ethtool_regs})

program did not crash
extracting C reproducer
testing compiled C program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$inet6-ioctl$sock_SIOCETHTOOL
program crashed: INFO: task hung in switchdev_deferred_process_work
a never seen crash title: INFO: task hung in switchdev_deferred_process_work, ignore
simplifying guilty program options
testing program (duration=6m0s, {Threaded:false Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$inet6-ioctl$sock_SIOCETHTOOL
detailed listing:
executing program 0:
r0 = socket$inet6(0xa, 0x1, 0x0)
ioctl$sock_SIOCETHTOOL(r0, 0x89f0, &(0x7f00000002c0)={'bridge0\x00', &(0x7f0000000340)=@ethtool_regs={0x4, 0x0, 0x1b, "aede62497cf56c9ab5bfd7b842f6b7ea6b8579d27d9c47d7da09f5"}})

program crashed: no output from test machine
a never seen crash title: no output from test machine, ignore
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$inet6-ioctl$sock_SIOCETHTOOL
detailed listing:
executing program 0:
r0 = socket$inet6(0xa, 0x1, 0x0)
ioctl$sock_SIOCETHTOOL(r0, 0x89f0, &(0x7f00000002c0)={'bridge0\x00', &(0x7f0000000340)=@ethtool_regs={0x4, 0x0, 0x1b, "aede62497cf56c9ab5bfd7b842f6b7ea6b8579d27d9c47d7da09f5"}})

program crashed: no output from test machine
a never seen crash title: no output from test machine, ignore
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$inet6-ioctl$sock_SIOCETHTOOL
detailed listing:
executing program 0:
r0 = socket$inet6(0xa, 0x1, 0x0)
ioctl$sock_SIOCETHTOOL(r0, 0x89f0, &(0x7f00000002c0)={'bridge0\x00', &(0x7f0000000340)=@ethtool_regs={0x4, 0x0, 0x1b, "aede62497cf56c9ab5bfd7b842f6b7ea6b8579d27d9c47d7da09f5"}})

program crashed: no output from test machine
validation run: crashed=true
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$inet6-ioctl$sock_SIOCETHTOOL
detailed listing:
executing program 0:
r0 = socket$inet6(0xa, 0x1, 0x0)
ioctl$sock_SIOCETHTOOL(r0, 0x89f0, &(0x7f00000002c0)={'bridge0\x00', &(0x7f0000000340)=@ethtool_regs={0x4, 0x0, 0x1b, "aede62497cf56c9ab5bfd7b842f6b7ea6b8579d27d9c47d7da09f5"}})

program crashed: INFO: task hung in inet_rtm_newaddr
validation run: crashed=true
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$inet6-ioctl$sock_SIOCETHTOOL
detailed listing:
executing program 0:
r0 = socket$inet6(0xa, 0x1, 0x0)
ioctl$sock_SIOCETHTOOL(r0, 0x89f0, &(0x7f00000002c0)={'bridge0\x00', &(0x7f0000000340)=@ethtool_regs={0x4, 0x0, 0x1b, "aede62497cf56c9ab5bfd7b842f6b7ea6b8579d27d9c47d7da09f5"}})

program crashed: INFO: task hung in linkwatch_event
validation run: crashed=true
reproducing took 1h7m48.19360064s
repro crashed as (corrupted=false):
INFO: task kworker/u8:2:42 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:2    state:D stack:22568 pid:42    tgid:42    ppid:2      task_flags:0x4208160 flags:0x00080000
Workqueue: events_unbound linkwatch_event
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5583 [inline]
 __schedule+0x17dd/0x5830 kernel/sched/core.c:7382
 __schedule_loop kernel/sched/core.c:7459 [inline]
 schedule+0x164/0x2b0 kernel/sched/core.c:7474
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7531
 __mutex_lock_common kernel/locking/mutex.c:726 [inline]
 __mutex_lock+0x7c4/0x15a0 kernel/locking/mutex.c:821
 linkwatch_event+0xe/0x60 net/core/link_watch.c:313
 process_one_work kernel/workqueue.c:3495 [inline]
 process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3578
 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3659
 kthread+0x38b/0x480 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
INFO: task kworker/u8:9:312 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:9    state:D stack:24136 pid:312   tgid:312   ppid:2      task_flags:0x4208060 flags:0x00080000
Workqueue: ipv6_addrconf addrconf_dad_work
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5583 [inline]
 __schedule+0x17dd/0x5830 kernel/sched/core.c:7382
 __schedule_loop kernel/sched/core.c:7459 [inline]
 schedule+0x164/0x2b0 kernel/sched/core.c:7474
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7531
 __mutex_lock_common kernel/locking/mutex.c:726 [inline]
 __mutex_lock+0x7c4/0x15a0 kernel/locking/mutex.c:821
 rtnl_net_lock include/linux/rtnetlink.h:134 [inline]
 addrconf_dad_work+0x116/0x15c0 net/ipv6/addrconf.c:4255
 process_one_work kernel/workqueue.c:3495 [inline]
 process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3578
 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3659
 kthread+0x38b/0x480 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
INFO: task syz.0.3199:12624 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.3199      state:D stack:28808 pid:12624 tgid:12622 ppid:5845   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5583 [inline]
 __schedule+0x17dd/0x5830 kernel/sched/core.c:7382
 __schedule_loop kernel/sched/core.c:7459 [inline]
 schedule+0x164/0x2b0 kernel/sched/core.c:7474
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7531
 __mutex_lock_common kernel/locking/mutex.c:726 [inline]
 __mutex_lock+0x7c4/0x15a0 kernel/locking/mutex.c:821
 rtnl_net_lock include/linux/rtnetlink.h:134 [inline]
 dev_ioctl+0x83c/0x1150 net/core/dev_ioctl.c:836
 sock_ioctl+0x753/0x7e0 net/socket.c:1374
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f887399f559
RSP: 002b:00007f8874847028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f8873c25fa0 RCX: 00007f887399f559
RDX: 00002000000002c0 RSI: 00000000000089f0 RDI: 0000000000000003
RBP: 00007f8873a36b50 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8873c26038 R14: 00007f8873c25fa0 R15: 00007ffd9185acd8
 </TASK>
INFO: task syz.4.3201:12628 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.3201      state:D stack:28808 pid:12628 tgid:12627 ppid:5855   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5583 [inline]
 __schedule+0x17dd/0x5830 kernel/sched/core.c:7382
 __schedule_loop kernel/sched/core.c:7459 [inline]
 schedule+0x164/0x2b0 kernel/sched/core.c:7474
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7531
 __mutex_lock_common kernel/locking/mutex.c:726 [inline]
 __mutex_lock+0x7c4/0x15a0 kernel/locking/mutex.c:821
 rtnl_net_lock include/linux/rtnetlink.h:134 [inline]
 dev_ioctl+0x83c/0x1150 net/core/dev_ioctl.c:836
 sock_ioctl+0x753/0x7e0 net/socket.c:1374
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f488eb9f559
RSP: 002b:00007f488fb17028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f488ee25fa0 RCX: 00007f488eb9f559
RDX: 00002000000002c0 RSI: 00000000000089f0 RDI: 0000000000000003
RBP: 00007f488ec36b50 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f488ee26038 R14: 00007f488ee25fa0 R15: 00007fff443d0aa8
 </TASK>

Showing all locks held in the system:
locks held by kthreadd/2: 2, last CPU#1:
 #0: ffffffff900b1950 (remove_cache_srcu){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:213 [inline]
 #0: ffffffff900b1950 (remove_cache_srcu){.+.+}-{0:0}, at: srcu_read_lock+0x27/0x60 include/linux/srcu.h:320
 #1: ffffffff8ff5a320 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
 #1: ffffffff8ff5a320 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #1: ffffffff8ff5a320 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1216 [inline]
 #1: ffffffff8ff5a320 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0x8f/0x2550 arch/x86/kernel/unwind_orc.c:495

final repro crashed as (corrupted=false):
INFO: task kworker/u8:2:42 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:2    state:D stack:22568 pid:42    tgid:42    ppid:2      task_flags:0x4208160 flags:0x00080000
Workqueue: events_unbound linkwatch_event
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5583 [inline]
 __schedule+0x17dd/0x5830 kernel/sched/core.c:7382
 __schedule_loop kernel/sched/core.c:7459 [inline]
 schedule+0x164/0x2b0 kernel/sched/core.c:7474
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7531
 __mutex_lock_common kernel/locking/mutex.c:726 [inline]
 __mutex_lock+0x7c4/0x15a0 kernel/locking/mutex.c:821
 linkwatch_event+0xe/0x60 net/core/link_watch.c:313
 process_one_work kernel/workqueue.c:3495 [inline]
 process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3578
 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3659
 kthread+0x38b/0x480 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
INFO: task kworker/u8:9:312 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:9    state:D stack:24136 pid:312   tgid:312   ppid:2      task_flags:0x4208060 flags:0x00080000
Workqueue: ipv6_addrconf addrconf_dad_work
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5583 [inline]
 __schedule+0x17dd/0x5830 kernel/sched/core.c:7382
 __schedule_loop kernel/sched/core.c:7459 [inline]
 schedule+0x164/0x2b0 kernel/sched/core.c:7474
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7531
 __mutex_lock_common kernel/locking/mutex.c:726 [inline]
 __mutex_lock+0x7c4/0x15a0 kernel/locking/mutex.c:821
 rtnl_net_lock include/linux/rtnetlink.h:134 [inline]
 addrconf_dad_work+0x116/0x15c0 net/ipv6/addrconf.c:4255
 process_one_work kernel/workqueue.c:3495 [inline]
 process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3578
 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3659
 kthread+0x38b/0x480 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
INFO: task syz.0.3199:12624 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.3199      state:D stack:28808 pid:12624 tgid:12622 ppid:5845   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5583 [inline]
 __schedule+0x17dd/0x5830 kernel/sched/core.c:7382
 __schedule_loop kernel/sched/core.c:7459 [inline]
 schedule+0x164/0x2b0 kernel/sched/core.c:7474
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7531
 __mutex_lock_common kernel/locking/mutex.c:726 [inline]
 __mutex_lock+0x7c4/0x15a0 kernel/locking/mutex.c:821
 rtnl_net_lock include/linux/rtnetlink.h:134 [inline]
 dev_ioctl+0x83c/0x1150 net/core/dev_ioctl.c:836
 sock_ioctl+0x753/0x7e0 net/socket.c:1374
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f887399f559
RSP: 002b:00007f8874847028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f8873c25fa0 RCX: 00007f887399f559
RDX: 00002000000002c0 RSI: 00000000000089f0 RDI: 0000000000000003
RBP: 00007f8873a36b50 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8873c26038 R14: 00007f8873c25fa0 R15: 00007ffd9185acd8
 </TASK>
INFO: task syz.4.3201:12628 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.3201      state:D stack:28808 pid:12628 tgid:12627 ppid:5855   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5583 [inline]
 __schedule+0x17dd/0x5830 kernel/sched/core.c:7382
 __schedule_loop kernel/sched/core.c:7459 [inline]
 schedule+0x164/0x2b0 kernel/sched/core.c:7474
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7531
 __mutex_lock_common kernel/locking/mutex.c:726 [inline]
 __mutex_lock+0x7c4/0x15a0 kernel/locking/mutex.c:821
 rtnl_net_lock include/linux/rtnetlink.h:134 [inline]
 dev_ioctl+0x83c/0x1150 net/core/dev_ioctl.c:836
 sock_ioctl+0x753/0x7e0 net/socket.c:1374
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f488eb9f559
RSP: 002b:00007f488fb17028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f488ee25fa0 RCX: 00007f488eb9f559
RDX: 00002000000002c0 RSI: 00000000000089f0 RDI: 0000000000000003
RBP: 00007f488ec36b50 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f488ee26038 R14: 00007f488ee25fa0 R15: 00007fff443d0aa8
 </TASK>

Showing all locks held in the system:
locks held by kthreadd/2: 2, last CPU#1:
 #0: ffffffff900b1950 (remove_cache_srcu){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:213 [inline]
 #0: ffffffff900b1950 (remove_cache_srcu){.+.+}-{0:0}, at: srcu_read_lock+0x27/0x60 include/linux/srcu.h:320
 #1: ffffffff8ff5a320 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
 #1: ffffffff8ff5a320 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #1: ffffffff8ff5a320 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1216 [inline]
 #1: ffffffff8ff5a320 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0x8f/0x2550 arch/x86/kernel/unwind_orc.c:495