Extracting prog: 6m27.239598078s
Minimizing prog: 27m13.571648169s
Simplifying prog options: 13m7.464371159s
Extracting C: 4m53.335201658s
Simplifying C: 1h13m3.53948226s


extracting reproducer from 1 programs
testing a last program of every proc
single: executing 1 programs separately with timeout 6m0s
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 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}}): socketpair$unix-ioctl$SIOCSIFHWADDR
detailed listing:
executing program 0:
socketpair$unix(0x1, 0x1, 0x0, &(0x7f00000000c0)={<r0=>0xffffffffffffffff})
ioctl$SIOCSIFHWADDR(r0, 0x89a2, &(0x7f0000000040)={'bridge0\x00', @random="1c00"})

program crashed: INFO: task kworker/NUM:NUM:NUM blocked for more than NUM seconds.
single: successfully extracted reproducer
found reproducer with 2 syscalls
minimizing guilty program
testing program (duration=6m42.18246663s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 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}}): socketpair$unix
detailed listing:
executing program 0:
socketpair$unix(0x1, 0x1, 0x0, &(0x7f00000000c0))

program did not crash
testing program (duration=6m42.18246663s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 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$SIOCSIFHWADDR
detailed listing:
executing program 0:
ioctl$SIOCSIFHWADDR(0xffffffffffffffff, 0x89a2, &(0x7f0000000040)={'bridge0\x00', @random="1c00"})

program did not crash
testing program (duration=6m42.18246663s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 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}}): socketpair$unix-ioctl$SIOCSIFHWADDR
detailed listing:
executing program 0:
socketpair$unix(0x1, 0x1, 0x0, 0x0)
ioctl$SIOCSIFHWADDR(0xffffffffffffffff, 0x89a2, &(0x7f0000000040)={'bridge0\x00', @random="1c00"})

program did not crash
testing program (duration=6m42.18246663s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 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}}): socketpair$unix-ioctl$SIOCSIFHWADDR
detailed listing:
executing program 0:
socketpair$unix(0x1, 0x1, 0x0, &(0x7f00000000c0)={<r0=>0xffffffffffffffff})
ioctl$SIOCSIFHWADDR(r0, 0x89a2, 0x0)

program did not crash
extracting C reproducer
testing compiled C program (duration=6m42.18246663s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 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}}): socketpair$unix-ioctl$SIOCSIFHWADDR
program crashed: INFO: task kworker/u8:NUM:NUM blocked for more than NUM seconds.
a never seen crash title: INFO: task kworker/u8:NUM:NUM blocked for more than NUM seconds., ignore
simplifying guilty program options
testing program (duration=6m42.18246663s, {Threaded:false Repeat:true RepeatTimes:0 Procs:4 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}}): socketpair$unix-ioctl$SIOCSIFHWADDR
detailed listing:
executing program 0:
socketpair$unix(0x1, 0x1, 0x0, &(0x7f00000000c0)={<r0=>0xffffffffffffffff})
ioctl$SIOCSIFHWADDR(r0, 0x89a2, &(0x7f0000000040)={'bridge0\x00', @random="1c00"})

program crashed: INFO: task kworker/u8:NUM:NUM blocked for more than NUM seconds.
a never seen crash title: INFO: task kworker/u8:NUM:NUM blocked for more than NUM seconds., ignore
testing program (duration=6m42.18246663s, {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}}): socketpair$unix-ioctl$SIOCSIFHWADDR
detailed listing:
executing program 0:
socketpair$unix(0x1, 0x1, 0x0, &(0x7f00000000c0)={<r0=>0xffffffffffffffff})
ioctl$SIOCSIFHWADDR(r0, 0x89a2, &(0x7f0000000040)={'bridge0\x00', @random="1c00"})

program crashed: INFO: task kworker/NUM:NUM:NUM blocked for more than NUM seconds.
extracting C reproducer
testing compiled C program (duration=6m42.18246663s, {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}}): socketpair$unix-ioctl$SIOCSIFHWADDR
program crashed: INFO: task kworker/NUM:NUM:NUM blocked for more than NUM seconds.
simplifying C reproducer
testing compiled C program (duration=6m42.18246663s, {Threaded:false 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}}): socketpair$unix-ioctl$SIOCSIFHWADDR
program crashed: INFO: task kworker/u8:NUM:NUM blocked for more than NUM seconds.
a never seen crash title: INFO: task kworker/u8:NUM:NUM blocked for more than NUM seconds., ignore
testing compiled C program (duration=6m42.18246663s, {Threaded:true Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox: SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:true Sysctl:true Swap:false UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socketpair$unix-ioctl$SIOCSIFHWADDR
program crashed: no output from test machine
a never seen crash title: no output from test machine, ignore
testing compiled C program (duration=6m42.18246663s, {Threaded:true Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false 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}}): socketpair$unix-ioctl$SIOCSIFHWADDR
program crashed: no output from test machine
a never seen crash title: no output from test machine, ignore
testing compiled C program (duration=6m42.18246663s, {Threaded:true Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:false 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}}): socketpair$unix-ioctl$SIOCSIFHWADDR
program crashed: no output from test machine
a never seen crash title: no output from test machine, ignore
testing compiled C program (duration=6m42.18246663s, {Threaded:true Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:false 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}}): socketpair$unix-ioctl$SIOCSIFHWADDR
program crashed: INFO: task kworker/u8:NUM:NUM blocked for more than NUM seconds.
a never seen crash title: INFO: task kworker/u8:NUM:NUM blocked for more than NUM seconds., ignore
testing compiled C program (duration=6m42.18246663s, {Threaded:true Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:false 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}}): socketpair$unix-ioctl$SIOCSIFHWADDR
program crashed: INFO: task kworker/NUM:NUM:NUM blocked for more than NUM seconds.
testing compiled C program (duration=6m42.18246663s, {Threaded:true Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:false BinfmtMisc:false 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}}): socketpair$unix-ioctl$SIOCSIFHWADDR
program crashed: INFO: task kworker/u8:NUM:NUM blocked for more than NUM seconds.
a never seen crash title: INFO: task kworker/u8:NUM:NUM blocked for more than NUM seconds., ignore
testing compiled C program (duration=6m42.18246663s, {Threaded:true Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:false BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:false 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}}): socketpair$unix-ioctl$SIOCSIFHWADDR
program crashed: INFO: task kworker/NUM:NUM:NUM blocked for more than NUM seconds.
testing compiled C program (duration=6m42.18246663s, {Threaded:true Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:false BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false 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}}): socketpair$unix-ioctl$SIOCSIFHWADDR
program crashed: INFO: task kworker/u8:NUM:NUM blocked for more than NUM seconds.
a never seen crash title: INFO: task kworker/u8:NUM:NUM blocked for more than NUM seconds., ignore
testing compiled C program (duration=6m42.18246663s, {Threaded:true Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:false BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:true Wifi:false IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socketpair$unix-ioctl$SIOCSIFHWADDR
program crashed: no output from test machine
a never seen crash title: no output from test machine, ignore
testing compiled C program (duration=6m42.18246663s, {Threaded:true Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:false BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:true Wifi:true IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socketpair$unix-ioctl$SIOCSIFHWADDR
program crashed: INFO: task kworker/NUM:NUM:NUM blocked for more than NUM seconds.
testing compiled C program (duration=6m42.18246663s, {Threaded:true Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:false BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:true Wifi:true IEEE802154:false Sysctl:true Swap:true UseTmpDir:false HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socketpair$unix-ioctl$SIOCSIFHWADDR
program crashed: INFO: task kworker/u8:NUM:NUM blocked for more than NUM seconds.
a never seen crash title: INFO: task kworker/u8:NUM:NUM blocked for more than NUM seconds., ignore
testing compiled C program (duration=6m42.18246663s, {Threaded:true Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:false BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:true Wifi:true IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:false Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socketpair$unix-ioctl$SIOCSIFHWADDR
program crashed: INFO: task kworker/NUM:NUM:NUM blocked for more than NUM seconds.
testing compiled C program (duration=6m42.18246663s, {Threaded:true Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:false BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:true Wifi:true IEEE802154:false Sysctl:false Swap:true UseTmpDir:true HandleSegv:false Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socketpair$unix-ioctl$SIOCSIFHWADDR
program crashed: INFO: task kworker/u8:NUM:NUM blocked for more than NUM seconds.
a never seen crash title: INFO: task kworker/u8:NUM:NUM blocked for more than NUM seconds., ignore
testing compiled C program (duration=6m42.18246663s, {Threaded:true Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:false BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:true Wifi:true IEEE802154:false Sysctl:true Swap:false UseTmpDir:true HandleSegv:false Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socketpair$unix-ioctl$SIOCSIFHWADDR
program crashed: INFO: task kworker/NUM:NUM:NUM blocked for more than NUM seconds.
testing program (duration=6m42.18246663s, {Threaded:true Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:false BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:true Wifi:true IEEE802154:false Sysctl:true Swap:false UseTmpDir:true HandleSegv:false Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socketpair$unix-ioctl$SIOCSIFHWADDR
detailed listing:
executing program 0:
socketpair$unix(0x1, 0x1, 0x0, &(0x7f00000000c0)={<r0=>0xffffffffffffffff})
ioctl$SIOCSIFHWADDR(r0, 0x89a2, &(0x7f0000000040)={'bridge0\x00', @random="1c00"})

program crashed: INFO: task kworker/u8:NUM:NUM blocked for more than NUM seconds.
validation run: crashed=true
testing program (duration=6m42.18246663s, {Threaded:true Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:false BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:true Wifi:true IEEE802154:false Sysctl:true Swap:false UseTmpDir:true HandleSegv:false Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socketpair$unix-ioctl$SIOCSIFHWADDR
detailed listing:
executing program 0:
socketpair$unix(0x1, 0x1, 0x0, &(0x7f00000000c0)={<r0=>0xffffffffffffffff})
ioctl$SIOCSIFHWADDR(r0, 0x89a2, &(0x7f0000000040)={'bridge0\x00', @random="1c00"})

program crashed: INFO: task kworker/u8:NUM:NUM blocked for more than NUM seconds.
validation run: crashed=true
testing program (duration=6m42.18246663s, {Threaded:true Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:false BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:true Wifi:true IEEE802154:false Sysctl:true Swap:false UseTmpDir:true HandleSegv:false Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socketpair$unix-ioctl$SIOCSIFHWADDR
detailed listing:
executing program 0:
socketpair$unix(0x1, 0x1, 0x0, &(0x7f00000000c0)={<r0=>0xffffffffffffffff})
ioctl$SIOCSIFHWADDR(r0, 0x89a2, &(0x7f0000000040)={'bridge0\x00', @random="1c00"})

program crashed: INFO: task kworker/u8:NUM:NUM blocked for more than NUM seconds.
validation run: crashed=true
reproducing took 2h16m11.771435869s
repro crashed as (corrupted=false):
INFO: task kworker/u8:0:12 blocked  for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:0    state:D stack:23040 pid:12    tgid:12    ppid:2      task_flags:0x4208060 flags:0x00080000
Workqueue: ipv6_addrconf addrconf_dad_work
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5295 [inline]
 __schedule+0x1585/0x5310 kernel/sched/core.c:6907
 __schedule_loop kernel/sched/core.c:6989 [inline]
 schedule+0x164/0x360 kernel/sched/core.c:7004
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7061
 __mutex_lock_common kernel/locking/mutex.c:692 [inline]
 __mutex_lock+0x7fe/0x1300 kernel/locking/mutex.c:776
 rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
 addrconf_dad_work+0x11e/0x14c0 net/ipv6/addrconf.c:4199
 process_one_work+0x949/0x1650 kernel/workqueue.c:3279
 process_scheduled_works kernel/workqueue.c:3362 [inline]
 worker_thread+0xb46/0x1140 kernel/workqueue.c:3443
 kthread+0x388/0x470 kernel/kthread.c:467

final repro crashed as (corrupted=false):
INFO: task kworker/u8:0:12 blocked  for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:0    state:D stack:23040 pid:12    tgid:12    ppid:2      task_flags:0x4208060 flags:0x00080000
Workqueue: ipv6_addrconf addrconf_dad_work
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5295 [inline]
 __schedule+0x1585/0x5310 kernel/sched/core.c:6907
 __schedule_loop kernel/sched/core.c:6989 [inline]
 schedule+0x164/0x360 kernel/sched/core.c:7004
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7061
 __mutex_lock_common kernel/locking/mutex.c:692 [inline]
 __mutex_lock+0x7fe/0x1300 kernel/locking/mutex.c:776
 rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
 addrconf_dad_work+0x11e/0x14c0 net/ipv6/addrconf.c:4199
 process_one_work+0x949/0x1650 kernel/workqueue.c:3279
 process_scheduled_works kernel/workqueue.c:3362 [inline]
 worker_thread+0xb46/0x1140 kernel/workqueue.c:3443
 kthread+0x388/0x470 kernel/kthread.c:467