Extracting prog: 5m50.356797282s Minimizing prog: 1h1m29.797530059s Simplifying prog options: 7m8.946503782s Extracting C: 5m13.691762175s 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, &(0x7f0000000000)='./sys\x00', 0x1ff) mount(0x0, &(0x7f0000000000)='./sys\x00', &(0x7f0000000040)='sysfs\x00', 0x0, 0x0) r0 = openat(0xffffffffffffff9c, &(0x7f0000000080)='./sys/bus/pci/devices/0000:00:03.0/config\x00', 0x2, 0x0) pwrite64(r0, &(0x7f00000004c0)="02155e6509625285a565d235077879efa843adf933737d90a5ab08d8cef99870ed0c4be6", 0x24, 0x2) program crashed: INFO: task hung in __ext4_find_entry 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, &(0x7f0000000000)='./sys\x00', 0x1ff) mount(0x0, &(0x7f0000000000)='./sys\x00', &(0x7f0000000040)='sysfs\x00', 0x0, 0x0) openat(0xffffffffffffff9c, &(0x7f0000000080)='./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, &(0x7f0000000000)='./sys\x00', 0x1ff) mount(0x0, &(0x7f0000000000)='./sys\x00', &(0x7f0000000040)='sysfs\x00', 0x0, 0x0) pwrite64(0xffffffffffffffff, &(0x7f00000004c0)="02155e6509625285a565d235077879efa843adf933737d90a5ab08d8cef99870ed0c4be6", 0x24, 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, &(0x7f0000000000)='./sys\x00', 0x1ff) r0 = openat(0xffffffffffffff9c, &(0x7f0000000080)='./sys/bus/pci/devices/0000:00:03.0/config\x00', 0x2, 0x0) pwrite64(r0, &(0x7f00000004c0)="02155e6509625285a565d235077879efa843adf933737d90a5ab08d8cef99870ed0c4be6", 0x24, 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, &(0x7f0000000000)='./sys\x00', &(0x7f0000000040)='sysfs\x00', 0x0, 0x0) r0 = openat(0xffffffffffffff9c, &(0x7f0000000080)='./sys/bus/pci/devices/0000:00:03.0/config\x00', 0x2, 0x0) pwrite64(r0, &(0x7f00000004c0)="02155e6509625285a565d235077879efa843adf933737d90a5ab08d8cef99870ed0c4be6", 0x24, 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, &(0x7f0000000000)='./sys\x00', &(0x7f0000000040)='sysfs\x00', 0x0, 0x0) r0 = openat(0xffffffffffffff9c, &(0x7f0000000080)='./sys/bus/pci/devices/0000:00:03.0/config\x00', 0x2, 0x0) pwrite64(r0, &(0x7f00000004c0)="02155e6509625285a565d235077879efa843adf933737d90a5ab08d8cef99870ed0c4be6", 0x24, 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, &(0x7f0000000000)='./sys\x00', 0x1ff) mount(0x0, 0x0, &(0x7f0000000040)='sysfs\x00', 0x0, 0x0) r0 = openat(0xffffffffffffff9c, &(0x7f0000000080)='./sys/bus/pci/devices/0000:00:03.0/config\x00', 0x2, 0x0) pwrite64(r0, &(0x7f00000004c0)="02155e6509625285a565d235077879efa843adf933737d90a5ab08d8cef99870ed0c4be6", 0x24, 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, &(0x7f0000000000)='./sys\x00', 0x1ff) mount(0x0, &(0x7f0000000000)='./sys\x00', 0x0, 0x0, 0x0) r0 = openat(0xffffffffffffff9c, &(0x7f0000000080)='./sys/bus/pci/devices/0000:00:03.0/config\x00', 0x2, 0x0) pwrite64(r0, &(0x7f00000004c0)="02155e6509625285a565d235077879efa843adf933737d90a5ab08d8cef99870ed0c4be6", 0x24, 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, &(0x7f0000000000)='./sys\x00', 0x1ff) mount(0x0, &(0x7f0000000000)='./sys\x00', &(0x7f0000000040)='sysfs\x00', 0x0, 0x0) r0 = openat(0xffffffffffffff9c, 0x0, 0x2, 0x0) pwrite64(r0, &(0x7f00000004c0)="02155e6509625285a565d235077879efa843adf933737d90a5ab08d8cef99870ed0c4be6", 0x24, 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, &(0x7f0000000000)='./sys\x00', 0x1ff) mount(0x0, &(0x7f0000000000)='./sys\x00', &(0x7f0000000040)='sysfs\x00', 0x0, 0x0) r0 = openat(0xffffffffffffff9c, &(0x7f0000000080)='./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, &(0x7f0000000000)='./sys\x00', 0x1ff) mount(0x0, &(0x7f0000000000)='./sys\x00', &(0x7f0000000040)='sysfs\x00', 0x0, 0x0) r0 = openat(0xffffffffffffff9c, &(0x7f0000000080)='./sys/bus/pci/devices/0000:00:03.0/config\x00', 0x2, 0x0) pwrite64(r0, &(0x7f00000004c0), 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 VM was preempted during C execution: failed to run command in VM: instance is preempted, retrying 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 do_get_write_access a never seen crash title: INFO: task hung in do_get_write_access, 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, &(0x7f0000000000)='./sys\x00', 0x1ff) mount(0x0, &(0x7f0000000000)='./sys\x00', &(0x7f0000000040)='sysfs\x00', 0x0, 0x0) r0 = openat(0xffffffffffffff9c, &(0x7f0000000080)='./sys/bus/pci/devices/0000:00:03.0/config\x00', 0x2, 0x0) pwrite64(r0, &(0x7f00000004c0)="02155e6509625285a565d235077879efa843adf933737d90a5ab08d8cef99870ed0c4be6", 0x24, 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: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, &(0x7f0000000000)='./sys\x00', 0x1ff) mount(0x0, &(0x7f0000000000)='./sys\x00', &(0x7f0000000040)='sysfs\x00', 0x0, 0x0) r0 = openat(0xffffffffffffff9c, &(0x7f0000000080)='./sys/bus/pci/devices/0000:00:03.0/config\x00', 0x2, 0x0) pwrite64(r0, &(0x7f00000004c0)="02155e6509625285a565d235077879efa843adf933737d90a5ab08d8cef99870ed0c4be6", 0x24, 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, &(0x7f0000000000)='./sys\x00', 0x1ff) mount(0x0, &(0x7f0000000000)='./sys\x00', &(0x7f0000000040)='sysfs\x00', 0x0, 0x0) r0 = openat(0xffffffffffffff9c, &(0x7f0000000080)='./sys/bus/pci/devices/0000:00:03.0/config\x00', 0x2, 0x0) pwrite64(r0, &(0x7f00000004c0)="02155e6509625285a565d235077879efa843adf933737d90a5ab08d8cef99870ed0c4be6", 0x24, 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, &(0x7f0000000000)='./sys\x00', 0x1ff) mount(0x0, &(0x7f0000000000)='./sys\x00', &(0x7f0000000040)='sysfs\x00', 0x0, 0x0) r0 = openat(0xffffffffffffff9c, &(0x7f0000000080)='./sys/bus/pci/devices/0000:00:03.0/config\x00', 0x2, 0x0) pwrite64(r0, &(0x7f00000004c0)="02155e6509625285a565d235077879efa843adf933737d90a5ab08d8cef99870ed0c4be6", 0x24, 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, &(0x7f0000000000)='./sys\x00', 0x1ff) mount(0x0, &(0x7f0000000000)='./sys\x00', &(0x7f0000000040)='sysfs\x00', 0x0, 0x0) r0 = openat(0xffffffffffffff9c, &(0x7f0000000080)='./sys/bus/pci/devices/0000:00:03.0/config\x00', 0x2, 0x0) pwrite64(r0, &(0x7f00000004c0)="02155e6509625285a565d235077879efa843adf933737d90a5ab08d8cef99870ed0c4be6", 0x24, 0x2) program crashed: INFO: task hung in do_get_write_access validation run: crashed=true reproducing took 1h30m53.330477656s repro crashed as (corrupted=false): INFO: task syz-executor:5761 blocked in I/O wait for more than 143 seconds. Not tainted syzkall Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:22376 pid:5761 tgid:5761 ppid:5754 task_flags:0x440140 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5526 [inline] __schedule+0x16d9/0x5700 kernel/sched/core.c:7277 __schedule_loop kernel/sched/core.c:7354 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7369 io_schedule+0x80/0xe0 kernel/sched/core.c:8213 bit_wait_io+0x11/0xd0 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+0x671/0x1090 fs/jbd2/transaction.c:1113 jbd2_journal_get_write_access+0x1d7/0x230 fs/jbd2/transaction.c:1263 __ext4_journal_get_write_access+0xf1/0x620 fs/ext4/ext4_jbd2.c:249 __ext4_new_inode+0x1355/0x3ec0 fs/ext4/ialloc.c:1101 ext4_mkdir+0x3ee/0xce0 fs/ext4/namei.c:3014 vfs_mkdir+0x408/0x620 fs/namei.c:5410 filename_mkdirat+0x289/0x520 fs/namei.c:5443 __do_sys_mkdirat fs/namei.c:5464 [inline] __se_sys_mkdirat+0x35/0x150 fs/namei.c:5461 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: 0033:0x7f502fc2cfc7 RSP: 002b:00007ffe58f0e0f8 EFLAGS: 00000206 ORIG_RAX: 0000000000000102 RAX: ffffffffffffffda RBX: 00007f502fcc4a7f RCX: 00007f502fc2cfc7 RDX: 00000000000001ff RSI: 00007f502fcc4a7f RDI: 00000000ffffff9c RBP: 00007ffe58f0e180 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 00007ffe58f0e188 R13: 0000000000000002 R14: 00007ffe58f0e368 R15: 0000000000000000 INFO: task syz-executor:5762 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:21512 pid:5762 tgid:5762 ppid:5753 task_flags:0x440140 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5526 [inline] __schedule+0x16d9/0x5700 kernel/sched/core.c:7277 __schedule_loop kernel/sched/core.c:7354 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7369 io_schedule+0x80/0xe0 kernel/sched/core.c:8213 bit_wait_io+0x11/0xd0 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+0x671/0x1090 fs/jbd2/transaction.c:1113 jbd2_journal_get_write_access+0x1d7/0x230 fs/jbd2/transaction.c:1263 __ext4_journal_get_write_access+0xf1/0x620 fs/ext4/ext4_jbd2.c:249 __ext4_new_inode+0x1355/0x3ec0 fs/ext4/ialloc.c:1101 ext4_mkdir+0x3ee/0xce0 fs/ext4/namei.c:3014 vfs_mkdir+0x408/0x620 fs/namei.c:5410 filename_mkdirat+0x289/0x520 fs/namei.c:5443 __do_sys_mkdirat fs/namei.c:5464 [inline] __se_sys_mkdirat+0x35/0x150 fs/namei.c:5461 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: 0033:0x7fbf8188cfc7 RSP: 002b:00007ffd0d46b288 EFLAGS: 00000202 ORIG_RAX: 0000000000000102 RAX: ffffffffffffffda RBX: 00007fbf81924a7f RCX: 00007fbf8188cfc7 RDX: 00000000000001ff RSI: 00007fbf81924a7f RDI: 00000000ffffff9c RBP: 00007ffd0d46b310 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 00007ffd0d46b318 R13: 0000000000000002 R14: 00007ffd0d46b4f8 R15: 0000000000000000 INFO: task syz.0.53:6104 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.0.53 state:D stack:24872 pid:6104 tgid:6104 ppid:5750 task_flags:0x440040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5526 [inline] __schedule+0x16d9/0x5700 kernel/sched/core.c:7277 __schedule_loop kernel/sched/core.c:7354 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7369 io_schedule+0x80/0xe0 kernel/sched/core.c:8213 bit_wait_io+0x11/0xd0 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+0x671/0x1090 fs/jbd2/transaction.c:1113 jbd2_journal_get_write_access+0x1d7/0x230 fs/jbd2/transaction.c:1263 __ext4_journal_get_write_access+0xf1/0x620 fs/ext4/ext4_jbd2.c:249 ext4_reserve_inode_write+0x294/0x360 fs/ext4/inode.c:6514 __ext4_mark_inode_dirty+0x146/0x7b0 fs/ext4/inode.c:6699 ext4_dirty_inode+0xd0/0x110 fs/ext4/inode.c:6736 __mark_inode_dirty+0x3a8/0x13b0 fs/fs-writeback.c:2729 generic_update_time fs/inode.c:2253 [inline] file_update_time_flags+0x39f/0x450 fs/inode.c:2483 ext4_page_mkwrite+0x225/0x1150 fs/ext4/inode.c:6902 do_page_mkwrite+0x14a/0x310 mm/memory.c:3816 do_shared_fault mm/memory.c:6076 [inline] do_fault mm/memory.c:6138 [inline] do_pte_missing+0x734/0x28f0 mm/memory.c:4700 handle_pte_fault mm/memory.c:6558 [inline] __handle_mm_fault mm/memory.c:6707 [inline] handle_mm_fault+0xf64/0x28c0 mm/memory.c:6876 do_user_addr_fault+0xa4f/0x1340 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: 0033:0x7feb6ea66871 RSP: 002b:00007ffe91e80ed0 EFLAGS: 00010202 RAX: 0000001b34064000 RBX: 0000000000000000 RCX: 000000000003fde8 RDX: 0000001b34063fff RSI: 0000000000000008 RDI: 00007feb6f955720 RBP: 00007feb6f955720 R08: 0000000000000000 R09: 00007feb6ee26038 R10: 00007feb6f955700 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000003 INFO: task syz.2.54:6106 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.2.54 state:D stack:26872 pid:6106 tgid:6106 ppid:5756 task_flags:0x440040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5526 [inline] __schedule+0x16d9/0x5700 kernel/sched/core.c:7277 __schedule_loop kernel/sched/core.c:7354 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7369 io_schedule+0x80/0xe0 kernel/sched/core.c:8213 bit_wait_io+0x11/0xd0 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+0x671/0x1090 fs/jbd2/transaction.c:1113 jbd2_journal_get_write_access+0x1d7/0x230 fs/jbd2/transaction.c:1263 __ext4_journal_get_write_access+0xf1/0x620 fs/ext4/ext4_jbd2.c:249 ext4_reserve_inode_write+0x294/0x360 fs/ext4/inode.c:6514 __ext4_mark_inode_dirty+0x146/0x7b0 fs/ext4/inode.c:6699 ext4_dirty_inode+0xd0/0x110 fs/ext4/inode.c:6736 __mark_inode_dirty+0x3a8/0x13b0 fs/fs-writeback.c:2729 generic_update_time fs/inode.c:2253 [inline] file_update_time_flags+0x39f/0x450 fs/inode.c:2483 ext4_page_mkwrite+0x225/0x1150 fs/ext4/inode.c:6902 do_page_mkwrite+0x14a/0x310 mm/memory.c:3816 do_shared_fault mm/memory.c:6076 [inline] do_fault mm/memory.c:6138 [inline] do_pte_missing+0x734/0x28f0 mm/memory.c:4700 handle_pte_fault mm/memory.c:6558 [inline] __handle_mm_fault mm/memory.c:6707 [inline] handle_mm_fault+0xf64/0x28c0 mm/memory.c:6876 do_user_addr_fault+0xa4f/0x1340 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: 0033:0x7f0defb9baa3 RSP: 002b:00007ffcdd502eb0 EFLAGS: 00010246 RAX: 000000000003fde8 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000001b34424000 RSI: 0000000000040000 RDI: 00007f0deff10708 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 00007ffcdd503140 INFO: task syz.1.55:6107 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.1.55 state:D stack:28264 pid:6107 tgid:6107 ppid:5751 task_flags:0x440040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5526 [inline] __schedule+0x16d9/0x5700 kernel/sched/core.c:7277 __schedule_loop kernel/sched/core.c:7354 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7369 io_schedule+0x80/0xe0 kernel/sched/core.c:8213 bit_wait_io+0x11/0xd0 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+0x671/0x1090 fs/jbd2/transaction.c:1113 jbd2_journal_get_write_access+0x1d7/0x230 fs/jbd2/transaction.c:1263 __ext4_journal_get_write_access+0xf1/0x620 fs/ext4/ext4_jbd2.c:249 ext4_reserve_inode_write+0x294/0x360 fs/ext4/inode.c:6514 __ext4_mark_inode_dirty+0x146/0x7b0 fs/ext4/inode.c:6699 ext4_dirty_inode+0xd0/0x110 fs/ext4/inode.c:6736 __mark_inode_dirty+0x3a8/0x13b0 fs/fs-writeback.c:2729 generic_update_time fs/inode.c:2253 [inline] file_update_time_flags+0x39f/0x450 fs/inode.c:2483 ext4_page_mkwrite+0x225/0x1150 fs/ext4/inode.c:6902 do_page_mkwrite+0x14a/0x310 mm/memory.c:3816 do_shared_fault mm/memory.c:6076 [inline] do_fault mm/memory.c:6138 [inline] do_pte_missing+0x734/0x28f0 mm/memory.c:4700 handle_pte_fault mm/memory.c:6558 [inline] __handle_mm_fault mm/memory.c:6707 [inline] handle_mm_fault+0xf64/0x28c0 mm/memory.c:6876 do_user_addr_fault+0xa4f/0x1340 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: 0033:0x7fe3b95abaa3 RSP: 002b:00007ffd9cb03f60 EFLAGS: 00010246 RAX: 000000000003fde8 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000001b34124000 RSI: 0000000000040000 RDI: 00007fe3b9920708 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 00007ffd9cb041f0 Showing all locks held in the system: locks held by khungtaskd/38: 1, last CPU#0: #0: ffffffff8e1c3c80 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #0: ffffffff8e1c3c80 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e1c3c80 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6871 locks held by getty/5338: 2, on CPU#1: #0: ffff888036c8a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900044cb2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x460/0x1360 drivers/tty/n_tty.c:2211 locks held by syz-executor/5615: 3, on CPU#1: #0: ffff888037b87030 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_trylock include/linux/mmap_lock.h:619 [inline] #0: ffff888037b87030 (&mm->mmap_lock){++++}-{4:4}, at: get_mmap_lock_carefully mm/mmap_lock.c:441 [inline] #0: ffff888037b87030 (&mm->mmap_lock){++++}-{4:4}, at: lock_mm_and_find_vma+0x36/0x340 mm/mmap_lock.c:501 #1: ffff888033ca2688 (sb_pagefaults){.+.+}-{0:0}, at: percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline] #1: ffff888033ca2688 (sb_pagefaults){.+.+}-{0:0}, at: __sb_start_write include/linux/fs/super.h:19 [inline] #1: ffff888033ca2688 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs/super.h:159 [inline] #1: ffff888033ca2688 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x203/0x1150 fs/ext4/inode.c:6901 #2: ffff888034472bb0 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1fbf/0x2200 fs/jbd2/transaction.c:444 locks held by syz-executor/5761: 3, on CPU#1: #0: ffff888033ca2510 (sb_writers#4){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:494 #1: ffff888040b669b0 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1069 [inline] #1: ffff888040b669b0 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2918 [inline] #1: ffff888040b669b0 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2942 [inline] #1: ffff888040b669b0 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: filename_create+0x200/0x370 fs/namei.c:5092 #2: ffff888034472bb0 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1fbf/0x2200 fs/jbd2/transaction.c:444 locks held by syz-executor/5762: 3, on CPU#1: #0: ffff888033ca2510 (sb_writers#4){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:494 #1: ffff88805bd90428 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1069 [inline] #1: ffff88805bd90428 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2918 [inline] #1: ffff88805bd90428 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2942 [inline] #1: ffff88805bd90428 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: filename_create+0x200/0x370 fs/namei.c:5092 #2: ffff888034472bb0 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1fbf/0x2200 fs/jbd2/transaction.c:444 locks held by syz.0.53/6104: 3, on CPU#0: #0: ffff88803dd656c8 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x1d1/0x500 mm/mmap_lock.c:310 #1: ffff888033ca2688 (sb_pagefaults){.+.+}-{0:0}, at: percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline] #1: ffff888033ca2688 (sb_pagefaults){.+.+}-{0:0}, at: __sb_start_write include/linux/fs/super.h:19 [inline] #1: ffff888033ca2688 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs/super.h:159 [inline] #1: ffff888033ca2688 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x203/0x1150 fs/ext4/inode.c:6901 #2: ffff888034472bb0 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1fbf/0x2200 fs/jbd2/transaction.c:444 locks held by syz.2.54/6106: 3, on CPU#0: #0: ffff888038271308 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x1d1/0x500 mm/mmap_lock.c:310 #1: ffff888033ca2688 (sb_pagefaults){.+.+}-{0:0}, at: percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline] #1: ffff888033ca2688 (sb_pagefaults){.+.+}-{0:0}, at: __sb_start_write include/linux/fs/super.h:19 [inline] #1: ffff888033ca2688 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs/super.h:159 [inline] #1: ffff888033ca2688 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x203/0x1150 fs/ext4/inode.c:6901 #2: ffff888034472bb0 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1fbf/0x2200 fs/jbd2/transaction.c:444 locks held by syz.1.55/6107: 3, on CPU#0: #0: ffff88803d472448 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x1d1/0x500 mm/mmap_lock.c:310 #1: ffff888033ca2688 (sb_pagefaults){.+.+}-{0:0}, at: percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline] #1: ffff888033ca2688 (sb_pagefaults){.+.+}-{0:0}, at: __sb_start_write include/linux/fs/super.h:19 [inline] #1: ffff888033ca2688 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs/super.h:159 [inline] #1: ffff888033ca2688 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x203/0x1150 fs/ext4/inode.c:6901 #2: ffff888034472bb0 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1fbf/0x2200 fs/jbd2/transaction.c:444 locks held by syz-executor/6109: 2, on CPU#1: #0: ffff888033ca2510 (sb_writers#4){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:494 #1: ffff8880409a9ab8 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1069 [inline] #1: ffff8880409a9ab8 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2918 [inline] #1: ffff8880409a9ab8 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2942 [inline] #1: ffff8880409a9ab8 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: filename_create+0x200/0x370 fs/namei.c:5092 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Call Trace: 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:353 [inline] watchdog+0xfd7/0x1030 kernel/hung_task.c:561 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 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 17 Comm: pr/ttyS0 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 RIP: 0010:io_serial_in+0x77/0xc0 drivers/tty/serial/8250/8250_port.c:409 Code: e8 6e fc 64 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 5f e7 d0 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:ffffc900001678b8 EFLAGS: 00000202 RAX: 1ffffffff33d4400 RBX: 00000000000003fd RCX: 0000000000000000 RDX: 00000000000003fd RSI: 0000000000000000 RDI: 0000000000000000 RBP: dffffc0000000000 R08: 0000000000000000 R09: 0000000000000000 R10: dffffc0000000000 R11: ffffffff85619c70 R12: dffffc0000000000 R13: 0000000000000000 R14: ffffffff99ea2220 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff888125ccb000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005623430a7a38 CR3: 000000004588c000 CR4: 00000000003526f0 Call Trace: serial_in drivers/tty/serial/8250/8250.h:128 [inline] serial_lsr_in drivers/tty/serial/8250/8250.h:150 [inline] wait_for_lsr+0x190/0x300 drivers/tty/serial/8250/8250_port.c:2013 serial8250_fifo_wait_for_lsr_thre drivers/tty/serial/8250/8250_port.c:3270 [inline] __serial8250_console_fifo_write+0xd0/0x3f0 drivers/tty/serial/8250/8250_port.c:3345 serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3378 [inline] __serial8250_console_write drivers/tty/serial/8250/8250_port.c:3429 [inline] serial8250_console_write+0xac5/0x1230 drivers/tty/serial/8250/8250_port.c:3493 nbcon_emit_next_record+0xef5/0x1a90 kernel/printk/nbcon.c:-1 nbcon_emit_one kernel/printk/nbcon.c:1157 [inline] nbcon_kthread_func+0x679/0x880 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 final repro crashed as (corrupted=false): INFO: task syz-executor:5761 blocked in I/O wait for more than 143 seconds. Not tainted syzkall Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:22376 pid:5761 tgid:5761 ppid:5754 task_flags:0x440140 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5526 [inline] __schedule+0x16d9/0x5700 kernel/sched/core.c:7277 __schedule_loop kernel/sched/core.c:7354 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7369 io_schedule+0x80/0xe0 kernel/sched/core.c:8213 bit_wait_io+0x11/0xd0 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+0x671/0x1090 fs/jbd2/transaction.c:1113 jbd2_journal_get_write_access+0x1d7/0x230 fs/jbd2/transaction.c:1263 __ext4_journal_get_write_access+0xf1/0x620 fs/ext4/ext4_jbd2.c:249 __ext4_new_inode+0x1355/0x3ec0 fs/ext4/ialloc.c:1101 ext4_mkdir+0x3ee/0xce0 fs/ext4/namei.c:3014 vfs_mkdir+0x408/0x620 fs/namei.c:5410 filename_mkdirat+0x289/0x520 fs/namei.c:5443 __do_sys_mkdirat fs/namei.c:5464 [inline] __se_sys_mkdirat+0x35/0x150 fs/namei.c:5461 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: 0033:0x7f502fc2cfc7 RSP: 002b:00007ffe58f0e0f8 EFLAGS: 00000206 ORIG_RAX: 0000000000000102 RAX: ffffffffffffffda RBX: 00007f502fcc4a7f RCX: 00007f502fc2cfc7 RDX: 00000000000001ff RSI: 00007f502fcc4a7f RDI: 00000000ffffff9c RBP: 00007ffe58f0e180 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 00007ffe58f0e188 R13: 0000000000000002 R14: 00007ffe58f0e368 R15: 0000000000000000 INFO: task syz-executor:5762 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:21512 pid:5762 tgid:5762 ppid:5753 task_flags:0x440140 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5526 [inline] __schedule+0x16d9/0x5700 kernel/sched/core.c:7277 __schedule_loop kernel/sched/core.c:7354 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7369 io_schedule+0x80/0xe0 kernel/sched/core.c:8213 bit_wait_io+0x11/0xd0 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+0x671/0x1090 fs/jbd2/transaction.c:1113 jbd2_journal_get_write_access+0x1d7/0x230 fs/jbd2/transaction.c:1263 __ext4_journal_get_write_access+0xf1/0x620 fs/ext4/ext4_jbd2.c:249 __ext4_new_inode+0x1355/0x3ec0 fs/ext4/ialloc.c:1101 ext4_mkdir+0x3ee/0xce0 fs/ext4/namei.c:3014 vfs_mkdir+0x408/0x620 fs/namei.c:5410 filename_mkdirat+0x289/0x520 fs/namei.c:5443 __do_sys_mkdirat fs/namei.c:5464 [inline] __se_sys_mkdirat+0x35/0x150 fs/namei.c:5461 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: 0033:0x7fbf8188cfc7 RSP: 002b:00007ffd0d46b288 EFLAGS: 00000202 ORIG_RAX: 0000000000000102 RAX: ffffffffffffffda RBX: 00007fbf81924a7f RCX: 00007fbf8188cfc7 RDX: 00000000000001ff RSI: 00007fbf81924a7f RDI: 00000000ffffff9c RBP: 00007ffd0d46b310 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 00007ffd0d46b318 R13: 0000000000000002 R14: 00007ffd0d46b4f8 R15: 0000000000000000 INFO: task syz.0.53:6104 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.0.53 state:D stack:24872 pid:6104 tgid:6104 ppid:5750 task_flags:0x440040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5526 [inline] __schedule+0x16d9/0x5700 kernel/sched/core.c:7277 __schedule_loop kernel/sched/core.c:7354 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7369 io_schedule+0x80/0xe0 kernel/sched/core.c:8213 bit_wait_io+0x11/0xd0 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+0x671/0x1090 fs/jbd2/transaction.c:1113 jbd2_journal_get_write_access+0x1d7/0x230 fs/jbd2/transaction.c:1263 __ext4_journal_get_write_access+0xf1/0x620 fs/ext4/ext4_jbd2.c:249 ext4_reserve_inode_write+0x294/0x360 fs/ext4/inode.c:6514 __ext4_mark_inode_dirty+0x146/0x7b0 fs/ext4/inode.c:6699 ext4_dirty_inode+0xd0/0x110 fs/ext4/inode.c:6736 __mark_inode_dirty+0x3a8/0x13b0 fs/fs-writeback.c:2729 generic_update_time fs/inode.c:2253 [inline] file_update_time_flags+0x39f/0x450 fs/inode.c:2483 ext4_page_mkwrite+0x225/0x1150 fs/ext4/inode.c:6902 do_page_mkwrite+0x14a/0x310 mm/memory.c:3816 do_shared_fault mm/memory.c:6076 [inline] do_fault mm/memory.c:6138 [inline] do_pte_missing+0x734/0x28f0 mm/memory.c:4700 handle_pte_fault mm/memory.c:6558 [inline] __handle_mm_fault mm/memory.c:6707 [inline] handle_mm_fault+0xf64/0x28c0 mm/memory.c:6876 do_user_addr_fault+0xa4f/0x1340 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: 0033:0x7feb6ea66871 RSP: 002b:00007ffe91e80ed0 EFLAGS: 00010202 RAX: 0000001b34064000 RBX: 0000000000000000 RCX: 000000000003fde8 RDX: 0000001b34063fff RSI: 0000000000000008 RDI: 00007feb6f955720 RBP: 00007feb6f955720 R08: 0000000000000000 R09: 00007feb6ee26038 R10: 00007feb6f955700 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000003 INFO: task syz.2.54:6106 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.2.54 state:D stack:26872 pid:6106 tgid:6106 ppid:5756 task_flags:0x440040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5526 [inline] __schedule+0x16d9/0x5700 kernel/sched/core.c:7277 __schedule_loop kernel/sched/core.c:7354 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7369 io_schedule+0x80/0xe0 kernel/sched/core.c:8213 bit_wait_io+0x11/0xd0 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+0x671/0x1090 fs/jbd2/transaction.c:1113 jbd2_journal_get_write_access+0x1d7/0x230 fs/jbd2/transaction.c:1263 __ext4_journal_get_write_access+0xf1/0x620 fs/ext4/ext4_jbd2.c:249 ext4_reserve_inode_write+0x294/0x360 fs/ext4/inode.c:6514 __ext4_mark_inode_dirty+0x146/0x7b0 fs/ext4/inode.c:6699 ext4_dirty_inode+0xd0/0x110 fs/ext4/inode.c:6736 __mark_inode_dirty+0x3a8/0x13b0 fs/fs-writeback.c:2729 generic_update_time fs/inode.c:2253 [inline] file_update_time_flags+0x39f/0x450 fs/inode.c:2483 ext4_page_mkwrite+0x225/0x1150 fs/ext4/inode.c:6902 do_page_mkwrite+0x14a/0x310 mm/memory.c:3816 do_shared_fault mm/memory.c:6076 [inline] do_fault mm/memory.c:6138 [inline] do_pte_missing+0x734/0x28f0 mm/memory.c:4700 handle_pte_fault mm/memory.c:6558 [inline] __handle_mm_fault mm/memory.c:6707 [inline] handle_mm_fault+0xf64/0x28c0 mm/memory.c:6876 do_user_addr_fault+0xa4f/0x1340 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: 0033:0x7f0defb9baa3 RSP: 002b:00007ffcdd502eb0 EFLAGS: 00010246 RAX: 000000000003fde8 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000001b34424000 RSI: 0000000000040000 RDI: 00007f0deff10708 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 00007ffcdd503140 INFO: task syz.1.55:6107 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.1.55 state:D stack:28264 pid:6107 tgid:6107 ppid:5751 task_flags:0x440040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5526 [inline] __schedule+0x16d9/0x5700 kernel/sched/core.c:7277 __schedule_loop kernel/sched/core.c:7354 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7369 io_schedule+0x80/0xe0 kernel/sched/core.c:8213 bit_wait_io+0x11/0xd0 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+0x671/0x1090 fs/jbd2/transaction.c:1113 jbd2_journal_get_write_access+0x1d7/0x230 fs/jbd2/transaction.c:1263 __ext4_journal_get_write_access+0xf1/0x620 fs/ext4/ext4_jbd2.c:249 ext4_reserve_inode_write+0x294/0x360 fs/ext4/inode.c:6514 __ext4_mark_inode_dirty+0x146/0x7b0 fs/ext4/inode.c:6699 ext4_dirty_inode+0xd0/0x110 fs/ext4/inode.c:6736 __mark_inode_dirty+0x3a8/0x13b0 fs/fs-writeback.c:2729 generic_update_time fs/inode.c:2253 [inline] file_update_time_flags+0x39f/0x450 fs/inode.c:2483 ext4_page_mkwrite+0x225/0x1150 fs/ext4/inode.c:6902 do_page_mkwrite+0x14a/0x310 mm/memory.c:3816 do_shared_fault mm/memory.c:6076 [inline] do_fault mm/memory.c:6138 [inline] do_pte_missing+0x734/0x28f0 mm/memory.c:4700 handle_pte_fault mm/memory.c:6558 [inline] __handle_mm_fault mm/memory.c:6707 [inline] handle_mm_fault+0xf64/0x28c0 mm/memory.c:6876 do_user_addr_fault+0xa4f/0x1340 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: 0033:0x7fe3b95abaa3 RSP: 002b:00007ffd9cb03f60 EFLAGS: 00010246 RAX: 000000000003fde8 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000001b34124000 RSI: 0000000000040000 RDI: 00007fe3b9920708 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 00007ffd9cb041f0 Showing all locks held in the system: locks held by khungtaskd/38: 1, last CPU#0: #0: ffffffff8e1c3c80 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #0: ffffffff8e1c3c80 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e1c3c80 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6871 locks held by getty/5338: 2, on CPU#1: #0: ffff888036c8a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900044cb2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x460/0x1360 drivers/tty/n_tty.c:2211 locks held by syz-executor/5615: 3, on CPU#1: #0: ffff888037b87030 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_trylock include/linux/mmap_lock.h:619 [inline] #0: ffff888037b87030 (&mm->mmap_lock){++++}-{4:4}, at: get_mmap_lock_carefully mm/mmap_lock.c:441 [inline] #0: ffff888037b87030 (&mm->mmap_lock){++++}-{4:4}, at: lock_mm_and_find_vma+0x36/0x340 mm/mmap_lock.c:501 #1: ffff888033ca2688 (sb_pagefaults){.+.+}-{0:0}, at: percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline] #1: ffff888033ca2688 (sb_pagefaults){.+.+}-{0:0}, at: __sb_start_write include/linux/fs/super.h:19 [inline] #1: ffff888033ca2688 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs/super.h:159 [inline] #1: ffff888033ca2688 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x203/0x1150 fs/ext4/inode.c:6901 #2: ffff888034472bb0 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1fbf/0x2200 fs/jbd2/transaction.c:444 locks held by syz-executor/5761: 3, on CPU#1: #0: ffff888033ca2510 (sb_writers#4){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:494 #1: ffff888040b669b0 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1069 [inline] #1: ffff888040b669b0 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2918 [inline] #1: ffff888040b669b0 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2942 [inline] #1: ffff888040b669b0 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: filename_create+0x200/0x370 fs/namei.c:5092 #2: ffff888034472bb0 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1fbf/0x2200 fs/jbd2/transaction.c:444 locks held by syz-executor/5762: 3, on CPU#1: #0: ffff888033ca2510 (sb_writers#4){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:494 #1: ffff88805bd90428 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1069 [inline] #1: ffff88805bd90428 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2918 [inline] #1: ffff88805bd90428 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2942 [inline] #1: ffff88805bd90428 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: filename_create+0x200/0x370 fs/namei.c:5092 #2: ffff888034472bb0 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1fbf/0x2200 fs/jbd2/transaction.c:444 locks held by syz.0.53/6104: 3, on CPU#0: #0: ffff88803dd656c8 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x1d1/0x500 mm/mmap_lock.c:310 #1: ffff888033ca2688 (sb_pagefaults){.+.+}-{0:0}, at: percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline] #1: ffff888033ca2688 (sb_pagefaults){.+.+}-{0:0}, at: __sb_start_write include/linux/fs/super.h:19 [inline] #1: ffff888033ca2688 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs/super.h:159 [inline] #1: ffff888033ca2688 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x203/0x1150 fs/ext4/inode.c:6901 #2: ffff888034472bb0 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1fbf/0x2200 fs/jbd2/transaction.c:444 locks held by syz.2.54/6106: 3, on CPU#0: #0: ffff888038271308 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x1d1/0x500 mm/mmap_lock.c:310 #1: ffff888033ca2688 (sb_pagefaults){.+.+}-{0:0}, at: percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline] #1: ffff888033ca2688 (sb_pagefaults){.+.+}-{0:0}, at: __sb_start_write include/linux/fs/super.h:19 [inline] #1: ffff888033ca2688 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs/super.h:159 [inline] #1: ffff888033ca2688 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x203/0x1150 fs/ext4/inode.c:6901 #2: ffff888034472bb0 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1fbf/0x2200 fs/jbd2/transaction.c:444 locks held by syz.1.55/6107: 3, on CPU#0: #0: ffff88803d472448 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x1d1/0x500 mm/mmap_lock.c:310 #1: ffff888033ca2688 (sb_pagefaults){.+.+}-{0:0}, at: percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline] #1: ffff888033ca2688 (sb_pagefaults){.+.+}-{0:0}, at: __sb_start_write include/linux/fs/super.h:19 [inline] #1: ffff888033ca2688 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs/super.h:159 [inline] #1: ffff888033ca2688 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x203/0x1150 fs/ext4/inode.c:6901 #2: ffff888034472bb0 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1fbf/0x2200 fs/jbd2/transaction.c:444 locks held by syz-executor/6109: 2, on CPU#1: #0: ffff888033ca2510 (sb_writers#4){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:494 #1: ffff8880409a9ab8 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1069 [inline] #1: ffff8880409a9ab8 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2918 [inline] #1: ffff8880409a9ab8 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2942 [inline] #1: ffff8880409a9ab8 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: filename_create+0x200/0x370 fs/namei.c:5092 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Call Trace: 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:353 [inline] watchdog+0xfd7/0x1030 kernel/hung_task.c:561 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 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 17 Comm: pr/ttyS0 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 RIP: 0010:io_serial_in+0x77/0xc0 drivers/tty/serial/8250/8250_port.c:409 Code: e8 6e fc 64 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 5f e7 d0 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:ffffc900001678b8 EFLAGS: 00000202 RAX: 1ffffffff33d4400 RBX: 00000000000003fd RCX: 0000000000000000 RDX: 00000000000003fd RSI: 0000000000000000 RDI: 0000000000000000 RBP: dffffc0000000000 R08: 0000000000000000 R09: 0000000000000000 R10: dffffc0000000000 R11: ffffffff85619c70 R12: dffffc0000000000 R13: 0000000000000000 R14: ffffffff99ea2220 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff888125ccb000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005623430a7a38 CR3: 000000004588c000 CR4: 00000000003526f0 Call Trace: serial_in drivers/tty/serial/8250/8250.h:128 [inline] serial_lsr_in drivers/tty/serial/8250/8250.h:150 [inline] wait_for_lsr+0x190/0x300 drivers/tty/serial/8250/8250_port.c:2013 serial8250_fifo_wait_for_lsr_thre drivers/tty/serial/8250/8250_port.c:3270 [inline] __serial8250_console_fifo_write+0xd0/0x3f0 drivers/tty/serial/8250/8250_port.c:3345 serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3378 [inline] __serial8250_console_write drivers/tty/serial/8250/8250_port.c:3429 [inline] serial8250_console_write+0xac5/0x1230 drivers/tty/serial/8250/8250_port.c:3493 nbcon_emit_next_record+0xef5/0x1a90 kernel/printk/nbcon.c:-1 nbcon_emit_one kernel/printk/nbcon.c:1157 [inline] nbcon_kthread_func+0x679/0x880 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