INFO: task syz.0.2776:11648 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.2776 state:D stack:27776 pid:11648 tgid:11647 ppid:5607 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5387 [inline]
__schedule+0x1681/0x54c0 kernel/sched/core.c:7188
__schedule_loop kernel/sched/core.c:7267 [inline]
rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7563
rt_mutex_slowlock_block+0x508/0x680 kernel/locking/rtmutex.c:1662
__rt_mutex_slowlock kernel/locking/rtmutex.c:1739 [inline]
__rt_mutex_slowlock_locked kernel/locking/rtmutex.c:1779 [inline]
rt_mutex_slowlock+0x2dc/0x780 kernel/locking/rtmutex.c:1819
__rt_mutex_lock kernel/locking/rtmutex.c:1834 [inline]
__mutex_lock_common kernel/locking/rtmutex_api.c:535 [inline]
mutex_lock_nested+0x168/0x1d0 kernel/locking/rtmutex_api.c:553
device_lock include/linux/device.h:1040 [inline]
usbdev_open+0x182/0x790 drivers/usb/core/devio.c:1054
chrdev_open+0x4d0/0x5f0 fs/char_dev.c:411
do_dentry_open+0x83d/0x13e0 fs/open.c:947
vfs_open+0x3b/0x350 fs/open.c:1079
do_open fs/namei.c:4699 [inline]
path_openat+0x2e43/0x38a0 fs/namei.c:4858
do_file_open+0x23e/0x4a0 fs/namei.c:4887
do_sys_openat2+0x113/0x200 fs/open.c:1364
do_sys_open fs/open.c:1370 [inline]
__do_sys_openat fs/open.c:1386 [inline]
__se_sys_openat fs/open.c:1381 [inline]
__x64_sys_openat+0x138/0x170 fs/open.c:1381
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc4783ed60e
RSP: 002b:00007fc47667db28 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fc47667e6c0 RCX: 00007fc4783ed60e
RDX: 0000000000101301 RSI: 00007fc47667dc00 RDI: ffffffffffffff9c
RBP: 00007fc47667dc00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: cccccccccccccccd
R13: 00007fc4786a6038 R14: 00007fc4786a5fa0 R15: 00007ffcb2357328
Showing all locks held in the system:
6 locks held by kworker/0:0/9:
1 lock held by khungtaskd/38:
#0: ffffffff8dfc8140 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8dfc8140 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
#0: ffffffff8dfc8140 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by kworker/1:2/819:
2 locks held by udevd/4959:
2 locks held by getty/5350:
#0: ffff8880370f30a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90003cbe2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13a0 drivers/tty/n_tty.c:2211
9 locks held by syz-executor/5604:
10 locks held by syz-executor/5605:
10 locks held by syz-executor/5608:
2 locks held by udevd/5897:
1 lock held by syz.0.2776/11648:
#0: ffff88802a330210 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1040 [inline]
#0: ffff88802a330210 (&dev->mutex){....}-{4:4}, at: usbdev_open+0x182/0x790 drivers/usb/core/devio.c:1054
1 lock held by syz.5.5029/16404:
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:162 [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+0xfd3/0x1030 kernel/hung_task.c:561
kthread+0x388/0x470 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 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 5605 Comm: syz-executor Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:check_preemption_disabled+0x3/0xe0 lib/smp_processor_id.c:13
Code: a7 8b 48 c7 c6 c0 4c a7 8b eb 1c 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 55 41 57 <41> 56 53 65 8b 05 a7 1f 4e 07 65 8b 0d 9c 1f 4e 07 f7 c1 ff ff ff
RSP: 0018:ffffc90004427210 EFLAGS: 00000283
RAX: 0000000000000000 RBX: ffffffff82329bea RCX: ffff88804071bd80
RDX: 0000000000000000 RSI: ffffffff8ba74cc0 RDI: ffffffff8ba74c80
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: fffff940002836f1 R12: dffffc0000000000
R13: ffffffff82329bea R14: ffffffff8dfc8200 R15: ffff88813fe4a140
FS: 000055557fcef500(0000) GS:ffff88812617c000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b32520ff8 CR3: 000000003f79c000 CR4: 00000000003526f0
Call Trace:
rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline]
rcu_is_watching+0x15/0xb0 kernel/rcu/tree.c:752
trace_lock_release include/trace/events/lock.h:69 [inline]
lock_release+0x4b/0x3c0 kernel/locking/lockdep.c:5879
rcu_lock_release include/linux/rcupdate.h:310 [inline]
rcu_read_unlock_sched include/linux/rcupdate.h:960 [inline]
pfn_valid+0x3b2/0x480 include/linux/mmzone.h:2291
page_table_check_set+0x25/0x510 mm/page_table_check.c:105
page_table_check_ptes_set include/linux/page_table_check.h:83 [inline]
set_ptes include/linux/pgtable.h:413 [inline]
__copy_present_ptes mm/memory.c:1102 [inline]
copy_present_ptes mm/memory.c:1181 [inline]
copy_pte_range mm/memory.c:1304 [inline]
copy_pmd_range+0x350b/0x5550 mm/memory.c:1392
copy_pud_range mm/memory.c:1429 [inline]
copy_p4d_range mm/memory.c:1453 [inline]
copy_page_range+0xaf4/0x1120 mm/memory.c:1539
dup_mmap+0xf4c/0x1d50 mm/mmap.c:1840
dup_mm kernel/fork.c:1534 [inline]
copy_mm+0x13b/0x4a0 kernel/fork.c:1586
copy_process+0x1f24/0x4460 kernel/fork.c:2262
kernel_clone+0x283/0x870 kernel/fork.c:2723
__do_sys_clone kernel/fork.c:2864 [inline]
__se_sys_clone kernel/fork.c:2848 [inline]
__x64_sys_clone+0x1b6/0x230 kernel/fork.c:2848
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1410745852
Code: 89 e7 e8 71 8b f7 ff 45 31 c0 31 d2 31 f6 64 48 8b 04 25 10 00 00 00 bf 11 00 20 01 4c 8d 90 d0 02 00 00 b8 38 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 66 89 c5 85 c0 75 3b 64 48 8b 04 25 10 00 00
RSP: 002b:00007fffa2f3db80 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007fffa2f3db80 RCX: 00007f1410745852
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 00007fffa2f3dd0c R08: 0000000000000000 R09: 0000000000000001
R10: 000055557fcef7d0 R11: 0000000000000246 R12: 0000000000000001
R13: 00000000000927c0 R14: 000000000007a84a R15: 00007fffa2f3dd60