Extracting prog: 6m8.428885581s
Minimizing prog: 1h2m0.650942396s
Simplifying prog options: 7m15.353398296s
Extracting C: 3m11.54275828s
Simplifying C: 0s


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: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}}): mkdirat-mount-openat-pwrite64
detailed listing:
executing program 0:
mkdirat(0xffffffffffffff9c, &(0x7f0000000100)='./sys\x00', 0x1ff)
mount(0x0, &(0x7f0000000140)='./sys\x00', &(0x7f0000000180)='sysfs\x00', 0x0, 0x0)
r0 = openat(0xffffffffffffff9c, &(0x7f00000001c0)='./sys/bus/pci/devices/0000:00:03.0/config\x00', 0x2, 0x0)
pwrite64(r0, &(0x7f0000000200)="02155e65", 0x4, 0x2)

program crashed: INFO: task hung in jbd2_journal_commit_transaction
single: successfully extracted reproducer
found reproducer with 4 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}}): mkdirat-mount-openat
detailed listing:
executing program 0:
mkdirat(0xffffffffffffff9c, &(0x7f0000000100)='./sys\x00', 0x1ff)
mount(0x0, &(0x7f0000000140)='./sys\x00', &(0x7f0000000180)='sysfs\x00', 0x0, 0x0)
openat(0xffffffffffffff9c, &(0x7f00000001c0)='./sys/bus/pci/devices/0000:00:03.0/config\x00', 0x2, 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}}): mkdirat-mount-pwrite64
detailed listing:
executing program 0:
mkdirat(0xffffffffffffff9c, &(0x7f0000000100)='./sys\x00', 0x1ff)
mount(0x0, &(0x7f0000000140)='./sys\x00', &(0x7f0000000180)='sysfs\x00', 0x0, 0x0)
pwrite64(0xffffffffffffffff, &(0x7f0000000200)="02155e65", 0x4, 0x2)

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}}): mkdirat-openat-pwrite64
detailed listing:
executing program 0:
mkdirat(0xffffffffffffff9c, &(0x7f0000000100)='./sys\x00', 0x1ff)
r0 = openat(0xffffffffffffff9c, &(0x7f00000001c0)='./sys/bus/pci/devices/0000:00:03.0/config\x00', 0x2, 0x0)
pwrite64(r0, &(0x7f0000000200)="02155e65", 0x4, 0x2)

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}}): mount-openat-pwrite64
detailed listing:
executing program 0:
mount(0x0, &(0x7f0000000140)='./sys\x00', &(0x7f0000000180)='sysfs\x00', 0x0, 0x0)
r0 = openat(0xffffffffffffff9c, &(0x7f00000001c0)='./sys/bus/pci/devices/0000:00:03.0/config\x00', 0x2, 0x0)
pwrite64(r0, &(0x7f0000000200)="02155e65", 0x4, 0x2)

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}}): mkdirat-mount-openat-pwrite64
detailed listing:
executing program 0:
mkdirat(0xffffffffffffff9c, 0x0, 0x1ff)
mount(0x0, &(0x7f0000000140)='./sys\x00', &(0x7f0000000180)='sysfs\x00', 0x0, 0x0)
r0 = openat(0xffffffffffffff9c, &(0x7f00000001c0)='./sys/bus/pci/devices/0000:00:03.0/config\x00', 0x2, 0x0)
pwrite64(r0, &(0x7f0000000200)="02155e65", 0x4, 0x2)

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}}): mkdirat-mount-openat-pwrite64
detailed listing:
executing program 0:
mkdirat(0xffffffffffffff9c, &(0x7f0000000100)='./sys\x00', 0x1ff)
mount(0x0, 0x0, &(0x7f0000000180)='sysfs\x00', 0x0, 0x0)
r0 = openat(0xffffffffffffff9c, &(0x7f00000001c0)='./sys/bus/pci/devices/0000:00:03.0/config\x00', 0x2, 0x0)
pwrite64(r0, &(0x7f0000000200)="02155e65", 0x4, 0x2)

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}}): mkdirat-mount-openat-pwrite64
detailed listing:
executing program 0:
mkdirat(0xffffffffffffff9c, &(0x7f0000000100)='./sys\x00', 0x1ff)
mount(0x0, &(0x7f0000000140)='./sys\x00', 0x0, 0x0, 0x0)
r0 = openat(0xffffffffffffff9c, &(0x7f00000001c0)='./sys/bus/pci/devices/0000:00:03.0/config\x00', 0x2, 0x0)
pwrite64(r0, &(0x7f0000000200)="02155e65", 0x4, 0x2)

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}}): mkdirat-mount-openat-pwrite64
detailed listing:
executing program 0:
mkdirat(0xffffffffffffff9c, &(0x7f0000000100)='./sys\x00', 0x1ff)
mount(0x0, &(0x7f0000000140)='./sys\x00', &(0x7f0000000180)='sysfs\x00', 0x0, 0x0)
r0 = openat(0xffffffffffffff9c, 0x0, 0x2, 0x0)
pwrite64(r0, &(0x7f0000000200)="02155e65", 0x4, 0x2)

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}}): mkdirat-mount-openat-pwrite64
detailed listing:
executing program 0:
mkdirat(0xffffffffffffff9c, &(0x7f0000000100)='./sys\x00', 0x1ff)
mount(0x0, &(0x7f0000000140)='./sys\x00', &(0x7f0000000180)='sysfs\x00', 0x0, 0x0)
r0 = openat(0xffffffffffffff9c, &(0x7f00000001c0)='./sys/bus/pci/devices/0000:00:03.0/config\x00', 0x2, 0x0)
pwrite64(r0, 0x0, 0x0, 0x2)

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}}): mkdirat-mount-openat-pwrite64
detailed listing:
executing program 0:
mkdirat(0xffffffffffffff9c, &(0x7f0000000100)='./sys\x00', 0x1ff)
mount(0x0, &(0x7f0000000140)='./sys\x00', &(0x7f0000000180)='sysfs\x00', 0x0, 0x0)
r0 = openat(0xffffffffffffff9c, &(0x7f00000001c0)='./sys/bus/pci/devices/0000:00:03.0/config\x00', 0x2, 0x0)
pwrite64(r0, &(0x7f0000000200), 0x0, 0x2)

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}}): mkdirat-mount-openat-pwrite64
program crashed: INFO: task hung in __rq_qos_throttle
a never seen crash title: INFO: task hung in __rq_qos_throttle, 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}}): mkdirat-mount-openat-pwrite64
detailed listing:
executing program 0:
mkdirat(0xffffffffffffff9c, &(0x7f0000000100)='./sys\x00', 0x1ff)
mount(0x0, &(0x7f0000000140)='./sys\x00', &(0x7f0000000180)='sysfs\x00', 0x0, 0x0)
r0 = openat(0xffffffffffffff9c, &(0x7f00000001c0)='./sys/bus/pci/devices/0000:00:03.0/config\x00', 0x2, 0x0)
pwrite64(r0, &(0x7f0000000200)="02155e65", 0x4, 0x2)

program crashed: INFO: task hung in corrupted
a never seen crash title: INFO: task hung in corrupted, 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}}): mkdirat-mount-openat-pwrite64
detailed listing:
executing program 0:
mkdirat(0xffffffffffffff9c, &(0x7f0000000100)='./sys\x00', 0x1ff)
mount(0x0, &(0x7f0000000140)='./sys\x00', &(0x7f0000000180)='sysfs\x00', 0x0, 0x0)
r0 = openat(0xffffffffffffff9c, &(0x7f00000001c0)='./sys/bus/pci/devices/0000:00:03.0/config\x00', 0x2, 0x0)
pwrite64(r0, &(0x7f0000000200)="02155e65", 0x4, 0x2)

program crashed: INFO: task hung in do_get_write_access
a never seen crash title: INFO: task hung in do_get_write_access, 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}}): mkdirat-mount-openat-pwrite64
detailed listing:
executing program 0:
mkdirat(0xffffffffffffff9c, &(0x7f0000000100)='./sys\x00', 0x1ff)
mount(0x0, &(0x7f0000000140)='./sys\x00', &(0x7f0000000180)='sysfs\x00', 0x0, 0x0)
r0 = openat(0xffffffffffffff9c, &(0x7f00000001c0)='./sys/bus/pci/devices/0000:00:03.0/config\x00', 0x2, 0x0)
pwrite64(r0, &(0x7f0000000200)="02155e65", 0x4, 0x2)

program crashed: INFO: task hung in do_get_write_access
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}}): mkdirat-mount-openat-pwrite64
detailed listing:
executing program 0:
mkdirat(0xffffffffffffff9c, &(0x7f0000000100)='./sys\x00', 0x1ff)
mount(0x0, &(0x7f0000000140)='./sys\x00', &(0x7f0000000180)='sysfs\x00', 0x0, 0x0)
r0 = openat(0xffffffffffffff9c, &(0x7f00000001c0)='./sys/bus/pci/devices/0000:00:03.0/config\x00', 0x2, 0x0)
pwrite64(r0, &(0x7f0000000200)="02155e65", 0x4, 0x2)

program crashed: INFO: task hung in jbd2_journal_commit_transaction
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}}): mkdirat-mount-openat-pwrite64
detailed listing:
executing program 0:
mkdirat(0xffffffffffffff9c, &(0x7f0000000100)='./sys\x00', 0x1ff)
mount(0x0, &(0x7f0000000140)='./sys\x00', &(0x7f0000000180)='sysfs\x00', 0x0, 0x0)
r0 = openat(0xffffffffffffff9c, &(0x7f00000001c0)='./sys/bus/pci/devices/0000:00:03.0/config\x00', 0x2, 0x0)
pwrite64(r0, &(0x7f0000000200)="02155e65", 0x4, 0x2)

program crashed: INFO: task hung in corrupted
validation run: crashed=true
reproducing took 1h30m6.179823745s
repro crashed as (corrupted=true):
INFO: task jbd2/sda1-8:4929 blocked in I/O wait for more than 143 seconds.
      Not tainted syzkaller #0

report is corrupted, running repro again
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}}): mkdirat-mount-openat-pwrite64
detailed listing:
executing program 0:
mkdirat(0xffffffffffffff9c, &(0x7f0000000100)='./sys\x00', 0x1ff)
mount(0x0, &(0x7f0000000140)='./sys\x00', &(0x7f0000000180)='sysfs\x00', 0x0, 0x0)
r0 = openat(0xffffffffffffff9c, &(0x7f00000001c0)='./sys/bus/pci/devices/0000:00:03.0/config\x00', 0x2, 0x0)
pwrite64(r0, &(0x7f0000000200)="02155e65", 0x4, 0x2)

program crashed: INFO: task hung in jbd2_journal_commit_transaction
final repro crashed as (corrupted=false):
INFO: task jbd2/sda1-8:4934 blocked in I/O wait for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:jbd2/sda1-8     state:D stack:26280 pid:4934  tgid:4934  ppid:2     
task:jbd2/sda1-8     state:D stack:26280 pid:4934  tgid:4934  ppid:2      task_flags:0x240040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5584 [inline]
 __schedule+0x1768/0x5780 kernel/sched/core.c:7389
 __schedule_loop kernel/sched/core.c:7466 [inline]
 schedule+0x164/0x2b0 kernel/sched/core.c:7481
 io_schedule+0x80/0xe0 kernel/sched/core.c:8153
 bit_wait_io+0x13/0x110 kernel/sched/wait_bit.c:258
 __wait_on_bit+0xac/0x2f0 kernel/sched/wait_bit.c:52
 out_of_line_wait_on_bit+0x13b/0x190 kernel/sched/wait_bit.c:67
 wait_on_buffer include/linux/buffer_head.h:476 [inline]
 jbd2_journal_commit_transaction+0x2f77/0x5cb0 fs/jbd2/commit.c:834
 kjournald2+0x3bc/0x740 fs/jbd2/journal.c:200
 kthread+0x38b/0x470 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-executor:5640 blocked in I/O wait for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:20992 pid:5640  tgid:5640  ppid:5634   task_flags:0x440100 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5584 [inline]
 __schedule+0x1768/0x5780 kernel/sched/core.c:7389
 __schedule_loop kernel/sched/core.c:7466 [inline]
 schedule+0x164/0x2b0 kernel/sched/core.c:7481
 io_schedule+0x80/0xe0 kernel/sched/core.c:8153
 bit_wait_io+0x13/0x110 kernel/sched/wait_bit.c:258
 __wait_on_bit+0xac/0x2f0 kernel/sched/wait_bit.c:52
 out_of_line_wait_on_bit+0x13b/0x190 kernel/sched/wait_bit.c:67
 wait_on_bit_io include/linux/wait_bit.h:106 [inline]
 do_get_write_access+0x667/0x10d0 fs/jbd2/transaction.c:1113
 jbd2_journal_get_write_access+0x1d7/0x230 fs/jbd2/transaction.c:1263
 __ext4_journal_get_write_access+0xec/0x620 fs/ext4/ext4_jbd2.c:253
 ext4_reserve_inode_write+0x294/0x360 fs/ext4/inode.c:7427
 __ext4_mark_inode_dirty+0x141/0x7e0 fs/ext4/inode.c:7618
 ext4_dirty_inode+0xd0/0x110 fs/ext4/inode.c:7655
 __mark_inode_dirty+0x3a8/0x13b0 fs/fs-writeback.c:2751
 generic_update_time fs/inode.c:2263 [inline]
 file_update_time_flags+0x39f/0x450 fs/inode.c:2493
 ext4_page_mkwrite+0x220/0x1490 fs/ext4/inode.c:7840
 do_page_mkwrite+0x14a/0x310 mm/memory.c:3889
 wp_page_shared mm/memory.c:4295 [inline]
 do_wp_page+0x2066/0x3e00 mm/memory.c:4518
 handle_pte_fault mm/memory.c:6692 [inline]
 __handle_mm_fault mm/memory.c:6817 [inline]
 handle_mm_fault+0xef9/0x2130 mm/memory.c:6984
 do_user_addr_fault+0xb35/0x1480 arch/x86/mm/fault.c:1343
 handle_page_fault arch/x86/mm/fault.c:1483 [inline]
 exc_page_fault+0x6a/0xc0 arch/x86/mm/fault.c:1536
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:595
RIP: 0033:0x7fcbc9e77e56
RSP: 002b:00007ffc33737318 EFLAGS: 00010202
RAX: 00007fcbc98f8000 RBX: 00005555846e0e30 RCX: fffffffffffffbf0
RDX: 00000000000000cf RSI: 00005555846df410 RDI: 00007fcbc98f8000
RBP: 00007ffc33737330 R08: 00007fcbca0fbe20 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 00005555846ed030
R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000000
 </TASK>
INFO: task syz.3.43:6192 blocked in I/O wait for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.43        state:D stack:25800 pid:6192  tgid:6192  ppid:5828   task_flags:0x440040 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5584 [inline]
 __schedule+0x1768/0x5780 kernel/sched/core.c:7389
 __schedule_loop kernel/sched/core.c:7466 [inline]
 schedule+0x164/0x2b0 kernel/sched/core.c:7481
 io_schedule+0x80/0xe0 kernel/sched/core.c:8153
 bit_wait_io+0x13/0x110 kernel/sched/wait_bit.c:258
 __wait_on_bit+0xac/0x2f0 kernel/sched/wait_bit.c:52
 out_of_line_wait_on_bit+0x13b/0x190 kernel/sched/wait_bit.c:67
 wait_on_bit_io include/linux/wait_bit.h:106 [inline]
 do_get_write_access+0x667/0x10d0 fs/jbd2/transaction.c:1113
 jbd2_journal_get_write_access+0x1d7/0x230 fs/jbd2/transaction.c:1263
 __ext4_journal_get_write_access+0xec/0x620 fs/ext4/ext4_jbd2.c:253
 ext4_reserve_inode_write+0x294/0x360 fs/ext4/inode.c:7427
 __ext4_mark_inode_dirty+0x141/0x7e0 fs/ext4/inode.c:7618
 ext4_dirty_inode+0xd0/0x110 fs/ext4/inode.c:7655
 __mark_inode_dirty+0x3a8/0x13b0 fs/fs-writeback.c:2751
 generic_update_time fs/inode.c:2263 [inline]
 file_update_time_flags+0x39f/0x450 fs/inode.c:2493
 ext4_page_mkwrite+0x220/0x1490 fs/ext4/inode.c:7840
 do_page_mkwrite+0x14a/0x310 mm/memory.c:3889
 do_shared_fault mm/memory.c:6188 [inline]
 do_fault mm/memory.c:6250 [inline]
 do_pte_missing+0x717/0x2970 mm/memory.c:4778
 handle_pte_fault mm/memory.c:6665 [inline]
 __handle_mm_fault mm/memory.c:6817 [inline]
 handle_mm_fault+0xd42/0x2130 mm/memory.c:6984
 do_user_addr_fault+0xb35/0x1480 arch/x86/mm/fault.c:1343
 handle_page_fault arch/x86/mm/fault.c:1483 [inline]
 exc_page_fault+0x6a/0xc0 arch/x86/mm/fault.c:1536
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:595
RIP: 0033:0x7f30b4ad7ff1
RSP: 002b:00007ffc164536a0 EFLAGS: 00010202
RAX: 0000001b30864000 RBX: 0000000000000000 RCX: 000000000003fde8
RDX: 0000001b30863fff RSI: 0000000000000008 RDI: 00007f30b59c5720
RBP: 00007f30b59c5720 R08: 0000000000000000 R09: 00007f30b4e96038
R10: 00007f30b59c5700 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000003
 </TASK>
INFO: task syz.1.44:6195 blocked in I/O wait for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.44        state:D stack:26296 pid:6195  tgid:6195  ppid:5824   task_flags:0x440040 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5584 [inline]
 __schedule+0x1768/0x5780 kernel/sched/core.c:7389
 __schedule_loop kernel/sched/core.c:7466 [inline]
 schedule+0x164/0x2b0 kernel/sched/core.c:7481
 io_schedule+0x80/0xe0 kernel/sched/core.c:8153
 bit_wait_io+0x13/0x110 kernel/sched/wait_bit.c:258
 __wait_on_bit+0xac/0x2f0 kernel/sched/wait_bit.c:52
 out_of_line_wait_on_bit+0x13b/0x190 kernel/sched/wait_bit.c:67
 wait_on_bit_io include/linux/wait_bit.h:106 [inline]
 do_get_write_access+0x667/0x10d0 fs/jbd2/transaction.c:1113
 jbd2_journal_get_write_access+0x1d7/0x230 fs/jbd2/transaction.c:1263
 __ext4_journal_get_write_access+0xec/0x620 fs/ext4/ext4_jbd2.c:253
 ext4_reserve_inode_write+0x294/0x360 fs/ext4/inode.c:7427
 __ext4_mark_inode_dirty+0x141/0x7e0 fs/ext4/inode.c:7618
 ext4_dirty_inode+0xd0/0x110 fs/ext4/inode.c:7655
 __mark_inode_dirty+0x3a8/0x13b0 fs/fs-writeback.c:2751
 generic_update_time fs/inode.c:2263 [inline]
 file_update_time_flags+0x39f/0x450 fs/inode.c:2493
 ext4_page_mkwrite+0x220/0x1490 fs/ext4/inode.c:7840
 do_page_mkwrite+0x14a/0x310 mm/memory.c:3889
 do_shared_fault mm/memory.c:6188 [inline]
 do_fault mm/memory.c:6250 [inline]
 do_pte_missing+0x717/0x2970 mm/memory.c:4778
 handle_pte_fault mm/memory.c:6665 [inline]
 __handle_mm_fault mm/memory.c:6817 [inline]
 handle_mm_fault+0xd42/0x2130 mm/memory.c:6984
 do_user_addr_fault+0xb35/0x1480 arch/x86/mm/fault.c:1343
 handle_page_fault arch/x86/mm/fault.c:1483 [inline]
 exc_page_fault+0x6a/0xc0 arch/x86/mm/fault.c:1536
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:595
RIP: 0033:0x7f8fda3eca63
RSP: 002b:00007fffda5110e0 EFLAGS: 00010246
RAX: 000000000003fde8 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000001b30524000 RSI: 0000000000040000 RDI: 00007f8fda769708
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 00007fffda511370
 </TASK>
INFO: task syz.4.45:6198 blocked in I/O wait for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.45        state:D stack:27616 pid:6198  tgid:6198  ppid:5830   task_flags:0x440040 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5584 [inline]
 __schedule+0x1768/0x5780 kernel/sched/core.c:7389
 __schedule_loop kernel/sched/core.c:7466 [inline]
 schedule+0x164/0x2b0 kernel/sched/core.c:7481
 io_schedule+0x80/0xe0 kernel/sched/core.c:8153
 bit_wait_io+0x13/0x110 kernel/sched/wait_bit.c:258
 __wait_on_bit+0xac/0x2f0 kernel/sched/wait_bit.c:52
 out_of_line_wait_on_bit+0x13b/0x190 kernel/sched/wait_bit.c:67
 wait_on_bit_io include/linux/wait_bit.h:106 [inline]
 do_get_write_access+0x667/0x10d0 fs/jbd2/transaction.c:1113
 jbd2_journal_get_write_access+0x1d7/0x230 fs/jbd2/transaction.c:1263
 __ext4_journal_get_write_access+0xec/0x620 fs/ext4/ext4_jbd2.c:253
 ext4_reserve_inode_write+0x294/0x360 fs/ext4/inode.c:7427
 __ext4_mark_inode_dirty+0x141/0x7e0 fs/ext4/inode.c:7618
 ext4_dirty_inode+0xd0/0x110 fs/ext4/inode.c:7655
 __mark_inode_dirty+0x3a8/0x13b0 fs/fs-writeback.c:2751
 generic_update_time fs/inode.c:2263 [inline]
 file_update_time_flags+0x39f/0x450 fs/inode.c:2493
 ext4_page_mkwrite+0x220/0x1490 fs/ext4/inode.c:7840
 do_page_mkwrite+0x14a/0x310 mm/memory.c:3889
 do_shared_fault mm/memory.c:6188 [inline]
 do_fault mm/memory.c:6250 [inline]
 do_pte_missing+0x717/0x2970 mm/memory.c:4778
 handle_pte_fault mm/memory.c:6665 [inline]
 __handle_mm_fault mm/memory.c:6817 [inline]
 handle_mm_fault+0xd42/0x2130 mm/memory.c:6984
 do_user_addr_fault+0xb35/0x1480 arch/x86/mm/fault.c:1343
 handle_page_fault arch/x86/mm/fault.c:1483 [inline]
 exc_page_fault+0x6a/0xc0 arch/x86/mm/fault.c:1536
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:595
RIP: 0033:0x7fde61b6ca63
RSP: 002b:00007ffded24ee40 EFLAGS: 00010246
RAX: 000000000003fde8 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000001b30b24000 RSI: 0000000000040000 RDI: 00007fde61ee9708
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 00007ffded24f0d0
 </TASK>

Showing all locks held in the system:
locks held by khungtaskd/39: 1, on CPU#0:
 #0: ffffffff8f3c15c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
 #0: ffffffff8f3c15c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #0: ffffffff8f3c15c0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6871
locks held by kworker/1:3/5337: 5, on CPU#1:
 #0: ffff88805bcee540 ((wq_completion)wg-kex-wg0#4){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
 #0: ffff88805bcee540 ((wq_completion)wg-kex-wg0#4){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #0: ffff88805bcee540 ((wq_completion)wg-kex-wg0#4){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3460 [inline]
 #0: ffff88805bcee540 ((wq_completion)wg-kex-wg0#4){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3578
 #1: ffffc900047dfc40 ((work_completion)(&({ do { const void __attribute__((btf_type_tag("percpu"))) *__vpp_verify = (typeof((worker) + 0))((void *)0); (void)__vpp_verify; } while (0); ((typeof((__typeof_unqual__(*((worker))) *)(( unsigned long)((worker)))))((unsigned long)((__typeof_unqual__(*((worker))) *)(( unsigned long)((worker)))) + (((__per_cpu_offset[(cpu)]))))); })->work)){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
 #1: ffffc900047dfc40 ((work_completion)(&({ do { const void __attribute__((btf_type_tag("percpu"))) *__vpp_verify = (typeof((worker) + 0))((void *)0); (void)__vpp_verify; } while (0); ((typeof((__typeof_unqual__(*((worker))) *)(( unsigned long)((worker)))))((unsigned long)((__typeof_unqual__(*((worker))) *)(( unsigned long)((worker)))) + (((__per_cpu_offset[(cpu)]))))); })->work)){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #1: ffffc900047dfc40 ((work_completion)(&({ do { const void __attribute__((btf_type_tag("percpu"))) *__vpp_verify = (typeof((worker) + 0))((void *)0); (void)__vpp_verify; } while (0); ((typeof((__typeof_unqual__(*((worker))) *)(( unsigned long)((worker)))))((unsigned long)((__typeof_unqual__(*((worker))) *)(( unsigned long)((worker)))) + (((__per_cpu_offset[(cpu)]))))); })->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3460 [inline]
 #1: ffffc900047dfc40 ((work_completion)(&({ do { const void __attribute__((btf_type_tag("percpu"))) *__vpp_verify = (typeof((worker) + 0))((void *)0); (void)__vpp_verify; } while (0); ((typeof((__typeof_unqual__(*((worker))) *)(( unsigned long)((worker)))))((unsigned long)((__typeof_unqual__(*((worker))) *)(( unsigned long)((worker)))) + (((__per_cpu_offset[(cpu)]))))); })->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3578
 #2: ffffffff8f3c15c0 (rcu_read_lock){....}-{1:3}, at: __local_bh_disable_ip+0x3d/0x420 kernel/softirq.c:186
 #3: ffffffff8f3c15c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
 #3: ffffffff8f3c15c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #3: ffffffff8f3c15c0 (rcu_read_lock){....}-{1:3}, at: process_backlog+0x261/0xc50 net/core/dev.c:6898
 #4: ffffffff8f3c15c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
 #4: ffffffff8f3c15c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #4: ffffffff8f3c15c0 (rcu_read_lock){....}-{1:3}, at: ip6_input+0x23/0x270 net/ipv6/ip6_input.c:544
locks held by getty/5362: 2, last CPU#1:
 #0: ffff88802b32c0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc900044c62e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x460/0x1360 drivers/tty/n_tty.c:2211
locks held by syz-executor/5640: 3, last CPU#1:
 #0: ffff888026cd5bc8 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x1d1/0x500 mm/mmap_lock.c:339
 #1: ffff8880371ce6a0 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs/super.h:159 [inline]
 #1: ffff8880371ce6a0 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x1ff/0x1490 fs/ext4/inode.c:7839
 #2: ffff8880371cabd0 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1fb0/0x21f0 fs/jbd2/transaction.c:444
locks held by kworker/1:4/5806: 5, on CPU#1:
 #0: ffff88805bcecd40 ((wq_completion)wg-kex-wg1#4){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
 #0: ffff88805bcecd40 ((wq_completion)wg-kex-wg1#4){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #0: ffff88805bcecd40 ((wq_completion)wg-kex-wg1#4){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3460 [inline]
 #0: ffff88805bcecd40 ((wq_completion)wg-kex-wg1#4){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3578
 #1: ffffc9000438fc40 ((work_completion)(&({ do { const void __attribute__((btf_type_tag("percpu"))) *__vpp_verify = (typeof((worker) + 0))((void *)0); (void)__vpp_verify; } while (0); ((typeof((__typeof_unqual__(*((worker))) *)(( unsigned long)((worker)))))((unsigned long)((__typeof_unqual__(*((worker))) *)(( unsigned long)((worker)))) + (((__per_cpu_offset[(cpu)]))))); })->work)){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
 #1: ffffc9000438fc40 ((work_completion)(&({ do { const void __attribute__((btf_type_tag("percpu"))) *__vpp_verify = (typeof((worker) + 0))((void *)0); (void)__vpp_verify; } while (0); ((typeof((__typeof_unqual__(*((worker))) *)(( unsigned long)((worker)))))((unsigned long)((__typeof_unqual__(*((worker))) *)(( unsigned long)((worker)))) + (((__per_cpu_offset[(cpu)]))))); })->work)){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #1: ffffc9000438fc40 ((work_completion)(&({ do { const void __attribute__((btf_type_tag("percpu"))) *__vpp_verify = (typeof((worker) + 0))((void *)0); (void)__vpp_verify; } while (0); ((typeof((__typeof_unqual__(*((worker))) *)(( unsigned long)((worker)))))((unsigned long)((__typeof_unqual__(*((worker))) *)(( unsigned long)((worker)))) + (((__per_cpu_offset[(cpu)]))))); })->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3460 [inline]
 #1: ffffc9000438fc40 ((work_completion)(&({ do { const void __attribute__((btf_type_tag("percpu"))) *__vpp_verify = (typeof((worker) + 0))((void *)0); (void)__vpp_verify; } while (0); ((typeof((__typeof_unqual__(*((worker))) *)(( unsigned long)((worker)))))((unsigned long)((__typeof_unqual__(*((worker))) *)(( unsigned long)((worker)))) + (((__per_cpu_offset[(cpu)]))))); })->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3578
 #2: ffff8880266d5938 (&handshake->lock){++++}-{4:4}, at: wg_noise_handshake_begin_session+0x38/0xbe0 drivers/net/wireguard/noise.c:821
 #3: ffffffff8f516f50 (remove_cache_srcu){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:249 [inline]
 #3: ffffffff8f516f50 (remove_cache_srcu){.+.+}-{0:0}, at: srcu_read_lock+0x27/0x60 include/linux/srcu.h:356
 #4: ffff8880b8543ed8 (&pcp->lock){+.+.}-{3:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
 #4: ffff8880b8543ed8 (&pcp->lock){+.+.}-{3:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #4: ffff8880b8543ed8 (&pcp->lock){+.+.}-{3:3}, at: __rt_spin_trylock kernel/locking/spinlock_rt.c:127 [inline]
 #4: ffff8880b8543ed8 (&pcp->lock){+.+.}-{3:3}, at: rt_spin_trylock+0x10c/0x2b0 kernel/locking/spinlock_rt.c:135
locks held by syz.3.43/6192: 3, last CPU#1:
 #0: ffff88805cdb9808 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x1d1/0x500 mm/mmap_lock.c:339
 #1: ffff8880371ce6a0 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs/super.h:159 [inline]
 #1: ffff8880371ce6a0 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x1ff/0x1490 fs/ext4/inode.c:7839
 #2: ffff8880371cabd0 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1fb0/0x21f0 fs/jbd2/transaction.c:444
locks held by syz.1.44/6195: 3, last CPU#1:
 #0: ffff8880387f9948 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x1d1/0x500 mm/mmap_lock.c:339
 #1: ffff8880371ce6a0 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs/super.h:159 [inline]
 #1: ffff8880371ce6a0 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x1ff/0x1490 fs/ext4/inode.c:7839
 #2: ffff8880371cabd0 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1fb0/0x21f0 fs/jbd2/transaction.c:444
locks held by syz.4.45/6198: 3, last CPU#1:
 #0: ffff88802dce51c8 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x1d1/0x500 mm/mmap_lock.c:339
 #1: ffff8880371ce6a0 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs/super.h:159 [inline]
 #1: ffff8880371ce6a0 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x1ff/0x1490 fs/ext4/inode.c:7839
 #2: ffff8880371cabd0 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1fb0/0x21f0 fs/jbd2/transaction.c:444

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

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 39 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/06/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:123
 nmi_trigger_cpumask_backtrace+0x17d/0x390 lib/nmi_backtrace.c:66
 trigger_all_cpu_backtrace include/linux/nmi.h:164 [inline]
 __sys_info lib/sys_info.c:157 [inline]
 sys_info+0x135/0x170 lib/sys_info.c:165
 check_hung_uninterruptible_tasks kernel/hung_task.c:377 [inline]
 watchdog+0x1073/0x10f0 kernel/hung_task.c:598
 kthread+0x38b/0x470 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>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 38 Comm: pr/ttyS0 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/06/2026
RIP: 0010:io_serial_in+0x77/0xc0 drivers/tty/serial/8250/8250_port.c:425
Code: e8 4e be 53 fc 44 89 f9 d3 e3 49 83 ee 80 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 3f 19 c7 fc 41 03 1e 89 da ec <0f> b6 c0 5b 41 5c 41 5e 41 5f c3 cc cc cc cc cc 44 89 f9 80 e1 07
RSP: 0018:ffffc90000af78b8 EFLAGS: 00000202
RAX: 1ffffffff362c700 RBX: 00000000000003fd RCX: 0000000000000000
RDX: 00000000000003fd RSI: 0000000000000000 RDI: 0000000000000000
RBP: dffffc0000000000 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffffff85742d70 R12: dffffc0000000000
R13: 0000000000000000 R14: ffffffff9b163cc0 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff88812470e000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055c9870b6660 CR3: 0000000038f88000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 serial_in drivers/tty/serial/8250/8250.h:134 [inline]
 serial_lsr_in drivers/tty/serial/8250/8250.h:156 [inline]
 wait_for_lsr+0x190/0x300 drivers/tty/serial/8250/8250_port.c:2036
 serial8250_fifo_wait_for_lsr_thre drivers/tty/serial/8250/8250_port.c:3294 [inline]
 __serial8250_console_fifo_write+0xd0/0x3f0 drivers/tty/serial/8250/8250_port.c:3369
 serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3402 [inline]
 __serial8250_console_write drivers/tty/serial/8250/8250_port.c:3456 [inline]
 serial8250_console_write+0xaa2/0x1220 drivers/tty/serial/8250/8250_port.c:3520
 nbcon_emit_next_record+0xef5/0x1a90 kernel/printk/nbcon.c:-1
 nbcon_emit_one kernel/printk/nbcon.c:1157 [inline]
 nbcon_kthread_func+0x6d9/0x8d0 kernel/printk/nbcon.c:1271
 kthread+0x38b/0x470 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>