INFO: task udevd:4325 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:25128 pid: 4325 ppid: 3560 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:2166 [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: 0033:0x7f418d786407
RSP: 002b:00007ffee4ab4470 EFLAGS: 00000202
ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 00007f418d698880 RCX: 00007f418d786407
RDX: 0000000000001000 RSI: 0000555ce4ee02b0 RDI: 0000000000000008
RBP: 00007f418d8ceff0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 000000000000000a
R13: 00007f418d8ceea0 R14: 0000000000000000 R15: 0000555ce4ef4f10
Showing all locks held in the system:
6 locks held by kworker/1:0/21:
#0: ffff88801b888d38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
#1: ffffc90000db7d00 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
#2: ffff8880240d9220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:764 [inline]
#2: ffff8880240d9220 (&dev->mutex){....}-{3:3}, at: hub_event+0x1a7/0x5560 drivers/usb/core/hub.c:5827
#3: ffff888077675220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:764 [inline]
#3: ffff888077675220 (&dev->mutex){....}-{3:3}, at: __device_attach+0x85/0x460 drivers/base/dd.c:954
#4: ffff8880200d51a8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:764 [inline]
#4: ffff8880200d51a8 (&dev->mutex){....}-{3:3}, at: __device_attach+0x85/0x460 drivers/base/dd.c:954
#5: ffffffff8bfccf90 (umhelper_sem){++++}-{3:3}, at: usermodehelper_read_trylock+0xe7/0x320 kernel/umh.c:217
1 lock held by khungtaskd/27:
#0: ffffffff8c11c720 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
2 locks held by kworker/0:2/1108:
#0: ffff888016872138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
#1: ffffc90004bb7d00 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
2 locks held by getty/3957:
#0: ffff88802bfee098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
#1: ffffc900025e62e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5ba/0x1a30 drivers/tty/n_tty.c:2158
1 lock held by syz-executor/4185:
#0: ffff888054e0c0e0 (&type->s_umount_key#86){+.+.}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:365
3 locks held by kworker/1:5/4247:
2 locks held by kworker/0:6/4259:
#0: ffff888016870938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
#1: ffffc9000339fd00 ((work_completion)(&fw_work->work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
4 locks held by kworker/u4:10/4321:
#0: ffff8880b913a358 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:475
#1: ffffc9000341fd00 (connector_reaper_work){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
#2: ffff888147768170 (&lo->lo_work_lock){....}-{2:2}, at: spin_lock_irq include/linux/spinlock.h:389 [inline]
#2: ffff888147768170 (&lo->lo_work_lock){....}-{2:2}, at: loop_process_work+0x165e/0x2480 drivers/block/loop.c:2278
#3: ffff8880b9127888 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x4d6/0x810 kernel/sched/psi.c:891
4 locks held by udevd/4325:
#0: ffff8880289cd668 (&p->lock){+.+.}-{3:3}, at: seq_read_iter+0xad/0xd50 fs/seq_file.c:182
#1: ffff88805ec12c88 (&of->mutex){+.+.}-{3:3}, at: kernfs_seq_start+0x51/0x3c0 fs/kernfs/file.c:112
#2: ffff88805fcccda0 (kn->active#32){++++}-{0:0}, at: kernfs_seq_start+0x71/0x3c0 fs/kernfs/file.c:113
#3: ffff888077675220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:764 [inline]
#3: ffff888077675220 (&dev->mutex){....}-{3:3}, at: uevent_show+0x17a/0x330 drivers/base/core.c:2408
4 locks held by kworker/1:9/4403:
2 locks held by kworker/0:11/4637:
#0: ffff888016870938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
#1: ffffc9000459fd00 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
1 lock held by dhcpcd/7247:
#0: ffff88807461d010 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline]
#0: ffff88807461d010 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: __sock_release net/socket.c:648 [inline]
#0: ffff88807461d010 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: sock_close+0x90/0x240 net/socket.c:1336
1 lock held by dhcpcd/7250:
#0: ffff88807461be10 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline]
#0: ffff88807461be10 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: __sock_release net/socket.c:648 [inline]
#0: ffff88807461be10 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: sock_close+0x90/0x240 net/socket.c:1336
1 lock held by dhcpcd/7252:
#0: ffff88807461ca10 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline]
#0: ffff88807461ca10 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: __sock_release net/socket.c:648 [inline]
#0: ffff88807461ca10 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: sock_close+0x90/0x240 net/socket.c:1336
2 locks held by dhcpcd/7253:
#0: ffff888056ced010 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline]
#0: ffff888056ced010 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: __sock_release net/socket.c:648 [inline]
#0: ffff888056ced010 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: sock_close+0x90/0x240 net/socket.c:1336
#1: ffffffff8c1211a8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:322 [inline]
#1: ffffffff8c1211a8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x320/0x6b0 kernel/rcu/tree_exp.h:845
1 lock held by dhcpcd/7254:
#0: ffff88807461ee10 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline]
#0: ffff88807461ee10 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: __sock_release net/socket.c:648 [inline]
#0: ffff88807461ee10 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: sock_close+0x90/0x240 net/socket.c:1336
1 lock held by dhcpcd/7257:
#0: ffff888022efb210 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline]
#0: ffff888022efb210 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: __sock_release net/socket.c:648 [inline]
#0: ffff888022efb210 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: sock_close+0x90/0x240 net/socket.c:1336
2 locks held by dhcpcd/7258:
#0: ffff88805f8c4120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1730 [inline]
#0: ffff88805f8c4120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x35/0xce0 net/packet/af_packet.c:3212
#1: ffffffff8c1211a8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:322 [inline]
#1: ffffffff8c1211a8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x320/0x6b0 kernel/rcu/tree_exp.h:845
=============================================
NMI backtrace for cpu 0
CPU: 0 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 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 7236 Comm: syz.6.580 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:pte_none arch/x86/include/asm/pgtable.h:727 [inline]
RIP: 0010:zap_pte_range mm/memory.c:1348 [inline]
RIP: 0010:zap_pmd_range mm/memory.c:1505 [inline]
RIP: 0010:zap_pud_range mm/memory.c:1534 [inline]
RIP: 0010:zap_p4d_range mm/memory.c:1555 [inline]
RIP: 0010:unmap_page_range+0x9da/0x2520 mm/memory.c:1576
Code: 89 e6 49 89 dc 49 c1 ec 03 48 b8 00 00 00 00 00 fc ff df 41 80 3c 04 00 74 08 48 89 df e8 be 86 10 00 4c 89 7c 24 08 4d 8b 3f <4c> 89 fe 48 83 e6 9f 31 ff e8 b8 22 cc ff 4c 89 f8 48 83 e0 9f 0f
RSP: 0018:ffffc90002f3f560 EFLAGS: 00000246
RAX: dffffc0000000000 RBX: ffff888054c045c0 RCX: ffff888020d8d940
RDX: 0000000000000000 RSI: 00000000000001fe RDI: 00000000000000b8
RBP: ffffc90002f3f6d0 R08: dffffc0000000000 R09: fffff940003eaaef
R10: fffff940003eaaef R11: 1ffffd40003eaaee R12: 1ffff1100a9808b8
R13: ffffc90002f3f840 R14: 00007fae128b9000 R15: 800000005562e027
FS: 0000000000000000(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555ce4efd130 CR3: 000000000be8e000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
unmap_vmas+0x11b/0x230 mm/memory.c:1653
exit_mmap+0x38f/0x5f0 mm/mmap.c:3216
__mmput+0x115/0x3b0 kernel/fork.c:1127
exit_mm+0x567/0x6c0 kernel/exit.c:550
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: 0033:0x7fae12dc3fc9
Code: Unable to access opcode bytes at RIP 0x7fae12dc3f9f.
RSP: 002b:00007fae1102b0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007fae1301afa8 RCX: 00007fae12dc3fc9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fae1301afa8
RBP: 00007fae1301afa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fae1301b038 R14: 00007ffd5d16ef80 R15: 00007ffd5d16f068