INFO: task udevd:4178 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:udevd state:D stack:23840 pid: 4178 ppid: 3563 flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11bb/0x4390 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537
__mutex_lock_common+0xc71/0x2390 kernel/locking/mutex.c:669
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
device_lock include/linux/device.h:764 [inline]
uevent_show+0x17a/0x330 drivers/base/core.c:2408
dev_attr_show+0x50/0xb0 drivers/base/core.c:2110
sysfs_kf_seq_show+0x316/0x4c0 fs/sysfs/file.c:61
seq_read_iter+0x49b/0xd50 fs/seq_file.c:230
call_read_iter include/linux/fs.h:2167 [inline]
new_sync_read fs/read_write.c:404 [inline]
vfs_read+0x725/0xcf0 fs/read_write.c:485
ksys_read+0x14d/0x250 fs/read_write.c:623
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fa9887e4407
RSP: 002b:00007fffc373f3a0 EFLAGS: 00000202 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 00007fa9886f6880 RCX: 00007fa9887e4407
RDX: 0000000000001000 RSI: 000055af44110a00 RDI: 0000000000000008
RBP: 00007fa98892cff0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 000000000000000a
R13: 00007fa98892cea0 R14: 0000000000000000 R15: 000055af44123e60
INFO: task syz.0.213:5697 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.213 state:D stack:25344 pid: 5697 ppid: 4191 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11bb/0x4390 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537
rwsem_down_read_slowpath+0x528/0x990 kernel/locking/rwsem.c:1055
__down_read_common kernel/locking/rwsem.c:1239 [inline]
__down_read kernel/locking/rwsem.c:1252 [inline]
down_read+0x96/0x2e0 kernel/locking/rwsem.c:1500
mmap_read_lock include/linux/mmap_lock.h:117 [inline]
exit_mm+0xda/0x6c0 kernel/exit.c:499
do_exit+0x5a1/0x20a0 kernel/exit.c:870
do_group_exit+0x12e/0x300 kernel/exit.c:997
get_signal+0x6ca/0x12c0 kernel/signal.c:2900
arch_do_signal_or_restart+0xc1/0x1300 arch/x86/kernel/signal.c:867
handle_signal_work kernel/entry/common.c:154 [inline]
exit_to_user_mode_loop+0x9e/0x130 kernel/entry/common.c:178
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214
__syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fcd9316f783
RSP: 002b:00007ffddeb044d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: fffffffffffffffc RBX: 00007fcd91bd76c0 RCX: 00007fcd9316f783
RDX: 0000000000000000 RSI: 0000000000021000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 00000000ffffffff R09: 0000000000000000
R10: 0000000000020022 R11: 0000000000000246 R12: 00007ffddeb04630
R13: ffffffffffffffc0 R14: 0000000000001000 R15: 0000000000000000
INFO: task syz.0.213:5698 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.213 state:D stack:24136 pid: 5698 ppid: 4191 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11bb/0x4390 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
rwsem_down_write_slowpath+0xc46/0x11f0 kernel/locking/rwsem.c:1165
mmap_write_lock include/linux/mmap_lock.h:71 [inline]
mmu_notifier_register+0x27/0xa0 mm/mmu_notifier.c:727
kvm_init_mmu_notifier virt/kvm/kvm_main.c:862 [inline]
kvm_create_vm virt/kvm/kvm_main.c:1156 [inline]
kvm_dev_ioctl_create_vm virt/kvm/kvm_main.c:4754 [inline]
kvm_dev_ioctl+0x13ac/0x2040 virt/kvm/kvm_main.c:4809
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:874 [inline]
__se_sys_ioctl+0xfa/0x170 fs/ioctl.c:860
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fcd9316f749
RSP: 002b:00007fcd913d6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fcd933c5fa0 RCX: 00007fcd9316f749
RDX: 0000000000000000 RSI: 000000000000ae01 RDI: 0000000000000009
RBP: 00007fcd931f3f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fcd933c6038 R14: 00007fcd933c5fa0 R15: 00007ffddeb04538
Showing all locks held in the system:
1 lock held by khungtaskd/27:
#0: ffffffff8c11c760 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
2 locks held by getty/3954:
#0: ffff88807f06b098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
#1: ffffc90002d032e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5ba/0x1a30 drivers/tty/n_tty.c:2158
1 lock held by syz-executor/4174:
#0: ffff88807d2df828 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:87 [inline]
#0: ffff88807d2df828 (&mm->mmap_lock){++++}-{3:3}, at: vm_mmap_pgoff+0x15d/0x2b0 mm/util.c:549
2 locks held by udevd/4176:
#0: ffffffff8c1a68f0 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mmap kernel/fork.c:503 [inline]
#0: ffffffff8c1a68f0 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mm kernel/fork.c:1466 [inline]
#0: ffffffff8c1a68f0 (dup_mmap_sem){.+.+}-{0:0}, at: copy_mm+0x21f/0x1380 kernel/fork.c:1518
#1: ffff88807a9b3228 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:87 [inline]
#1: ffff88807a9b3228 (&mm->mmap_lock){++++}-{3:3}, at: dup_mmap kernel/fork.c:504 [inline]
#1: ffff88807a9b3228 (&mm->mmap_lock){++++}-{3:3}, at: dup_mm kernel/fork.c:1466 [inline]
#1: ffff88807a9b3228 (&mm->mmap_lock){++++}-{3:3}, at: copy_mm+0x238/0x1380 kernel/fork.c:1518
4 locks held by udevd/4178:
#0: ffff888063bebe80 (&p->lock){+.+.}-{3:3}, at: seq_read_iter+0xad/0xd50 fs/seq_file.c:182
#1: ffff88805fe63088 (&of->mutex){+.+.}-{3:3}, at: kernfs_seq_start+0x51/0x3c0 fs/kernfs/file.c:112
#2: ffff88806029bcb8 (kn->active#32){++++}-{0:0}, at: kernfs_seq_start+0x71/0x3c0 fs/kernfs/file.c:113
#3: ffff88806232d220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:764 [inline]
#3: ffff88806232d220 (&dev->mutex){....}-{3:3}, at: uevent_show+0x17a/0x330 drivers/base/core.c:2408
2 locks held by syz-executor/4186:
#0: ffffffff8c1a68f0 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mmap kernel/fork.c:503 [inline]
#0: ffffffff8c1a68f0 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mm kernel/fork.c:1466 [inline]
#0: ffffffff8c1a68f0 (dup_mmap_sem){.+.+}-{0:0}, at: copy_mm+0x21f/0x1380 kernel/fork.c:1518
#1: ffff88807a332b28 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:87 [inline]
#1: ffff88807a332b28 (&mm->mmap_lock){++++}-{3:3}, at: dup_mmap kernel/fork.c:504 [inline]
#1: ffff88807a332b28 (&mm->mmap_lock){++++}-{3:3}, at: dup_mm kernel/fork.c:1466 [inline]
#1: ffff88807a332b28 (&mm->mmap_lock){++++}-{3:3}, at: copy_mm+0x238/0x1380 kernel/fork.c:1518
2 locks held by syz-executor/4193:
#0: ffffffff8c1a68f0 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mmap kernel/fork.c:503 [inline]
#0: ffffffff8c1a68f0 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mm kernel/fork.c:1466 [inline]
#0: ffffffff8c1a68f0 (dup_mmap_sem){.+.+}-{0:0}, at: copy_mm+0x21f/0x1380 kernel/fork.c:1518
#1: ffff88807a9b5c28 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:87 [inline]
#1: ffff88807a9b5c28 (&mm->mmap_lock){++++}-{3:3}, at: dup_mmap kernel/fork.c:504 [inline]
#1: ffff88807a9b5c28 (&mm->mmap_lock){++++}-{3:3}, at: dup_mm kernel/fork.c:1466 [inline]
#1: ffff88807a9b5c28 (&mm->mmap_lock){++++}-{3:3}, at: copy_mm+0x238/0x1380 kernel/fork.c:1518
1 lock held by udevd/4579:
#0: ffff88807c1dea28 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:87 [inline]
#0: ffff88807c1dea28 (&mm->mmap_lock){++++}-{3:3}, at: vm_mmap_pgoff+0x15d/0x2b0 mm/util.c:549
2 locks held by syz-executor/4584:
#0: ffffffff8c1a68f0 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mmap kernel/fork.c:503 [inline]
#0: ffffffff8c1a68f0 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mm kernel/fork.c:1466 [inline]
#0: ffffffff8c1a68f0 (dup_mmap_sem){.+.+}-{0:0}, at: copy_mm+0x21f/0x1380 kernel/fork.c:1518
#1: ffff88807c1dce28 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:87 [inline]
#1: ffff88807c1dce28 (&mm->mmap_lock){++++}-{3:3}, at: dup_mmap kernel/fork.c:504 [inline]
#1: ffff88807c1dce28 (&mm->mmap_lock){++++}-{3:3}, at: dup_mm kernel/fork.c:1466 [inline]
#1: ffff88807c1dce28 (&mm->mmap_lock){++++}-{3:3}, at: copy_mm+0x238/0x1380 kernel/fork.c:1518
2 locks held by syz-executor/4740:
#0: ffffffff8c1a68f0 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mmap kernel/fork.c:503 [inline]
#0: ffffffff8c1a68f0 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mm kernel/fork.c:1466 [inline]
#0: ffffffff8c1a68f0 (dup_mmap_sem){.+.+}-{0:0}, at: copy_mm+0x21f/0x1380 kernel/fork.c:1518
#1: ffff88807a335c28 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:87 [inline]
#1: ffff88807a335c28 (&mm->mmap_lock){++++}-{3:3}, at: dup_mmap kernel/fork.c:504 [inline]
#1: ffff88807a335c28 (&mm->mmap_lock){++++}-{3:3}, at: dup_mm kernel/fork.c:1466 [inline]
#1: ffff88807a335c28 (&mm->mmap_lock){++++}-{3:3}, at: copy_mm+0x238/0x1380 kernel/fork.c:1518
5 locks held by kworker/1:20/5670:
#0: ffff88801b66f138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
#1: ffffc90002eefd00 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
#2: ffff88802407f220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:764 [inline]
#2: ffff88802407f220 (&dev->mutex){....}-{3:3}, at: hub_event+0x1a7/0x5560 drivers/usb/core/hub.c:5827
#3: ffff88806232d220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:764 [inline]
#3: ffff88806232d220 (&dev->mutex){....}-{3:3}, at: __device_attach+0x85/0x460 drivers/base/dd.c:954
#4: ffff88801f7631a8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:764 [inline]
#4: ffff88801f7631a8 (&dev->mutex){....}-{3:3}, at: __device_attach+0x85/0x460 drivers/base/dd.c:954
2 locks held by kworker/u4:11/5673:
#0: ffff888016879138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
#1: ffffc90003c3fd00 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
1 lock held by syz.0.213/5697:
#0: ffff88802bdb6328 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_lock include/linux/mmap_lock.h:117 [inline]
#0: ffff88802bdb6328 (&mm->mmap_lock){++++}-{3:3}, at: exit_mm+0xda/0x6c0 kernel/exit.c:499
1 lock held by syz.0.213/5698:
#0: ffff88802bdb6328 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock include/linux/mmap_lock.h:71 [inline]
#0: ffff88802bdb6328 (&mm->mmap_lock){++++}-{3:3}, at: mmu_notifier_register+0x27/0xa0 mm/mmu_notifier.c:727
1 lock held by sed/5700:
#0: ffff88807e341628 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:87 [inline]
#0: ffff88807e341628 (&mm->mmap_lock){++++}-{3:3}, at: setup_arg_pages+0x2db/0xa20 fs/exec.c:797
1 lock held by modprobe/5702:
#0: ffff88807e341d28 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:87 [inline]
#0: ffff88807e341d28 (&mm->mmap_lock){++++}-{3:3}, at: setup_arg_pages+0x2db/0xa20 fs/exec.c:797
=============================================
NMI backtrace for cpu 1
CPU: 1 PID: 27 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Call Trace:
dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106
nmi_cpu_backtrace+0x397/0x3d0 lib/nmi_backtrace.c:111
nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline]
watchdog+0xe0f/0xe50 kernel/hung_task.c:369
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline]
NMI backtrace for cpu 0 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline]
NMI backtrace for cpu 0 skipped: idling at default_idle+0xb/0x10 arch/x86/kernel/process.c:729