INFO: task syz.4.2589:11122 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.2589 state:D stack:28296 pid:11122 tgid:11119 ppid:5602 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x16dc/0x5500 kernel/sched/core.c:7234
__schedule_loop kernel/sched/core.c:7311 [inline]
rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7607
rt_mutex_slowlock_block+0x55c/0x680 kernel/locking/rtmutex.c:1670
__rt_mutex_slowlock kernel/locking/rtmutex.c:1747 [inline]
__rt_mutex_slowlock_locked kernel/locking/rtmutex.c:1787 [inline]
rt_mutex_slowlock+0x2d4/0x780 kernel/locking/rtmutex.c:1827
__rt_mutex_lock kernel/locking/rtmutex.c:1842 [inline]
__mutex_lock_common kernel/locking/rtmutex_api.c:560 [inline]
mutex_lock_nested+0x168/0x1d0 kernel/locking/rtmutex_api.c:578
device_lock include/linux/device.h:1102 [inline]
usbdev_open+0x151/0x790 drivers/usb/core/devio.c:1054
chrdev_open+0x4dc/0x600 fs/char_dev.c:411
do_dentry_open+0x849/0x1420 fs/open.c:947
vfs_open+0x3b/0x350 fs/open.c:1052
do_open fs/namei.c:4700 [inline]
path_openat+0x2e60/0x3850 fs/namei.c:4863
do_file_open+0x23e/0x4a0 fs/namei.c:4892
do_sys_openat2+0x115/0x200 fs/open.c:1368
do_sys_open fs/open.c:1374 [inline]
__do_sys_openat fs/open.c:1390 [inline]
__se_sys_openat fs/open.c:1385 [inline]
__x64_sys_openat+0x138/0x170 fs/open.c:1385
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f94a511e6ce
RSP: 002b:00007f94a33b5b28 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f94a33b66c0 RCX: 00007f94a511e6ce
RDX: 0000000000000002 RSI: 00007f94a33b5c00 RDI: ffffffffffffff9c
RBP: 00007f94a33b5c00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: cccccccccccccccd
R13: 00007f94a53e6038 R14: 00007f94a53e5fa0 R15: 00007fff43d933b8
Showing all locks held in the system:
1 lock held by khungtaskd/38:
#0: ffffffff8e1c3000 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8e1c3000 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#0: ffffffff8e1c3000 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
3 locks held by kworker/u8:7/306:
1 lock held by udevd/4969:
2 locks held by getty/5354:
#0: ffff888035fdb0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90003cc62e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x460/0x1360 drivers/tty/n_tty.c:2211
5 locks held by kworker/1:6/5741:
5 locks held by kworker/0:6/5742:
#0: ffff8880222ae938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
#0: ffff8880222ae938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
#1: ffffc90005fd7c40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
#1: ffffc90005fd7c40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
#2: ffff88802aa24210 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline]
#2: ffff88802aa24210 (&dev->mutex){....}-{4:4}, at: hub_event+0x187/0x4cf0 drivers/usb/core/hub.c:5899
#3: ffff888064bd6210 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline]
#3: ffff888064bd6210 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x450 drivers/base/dd.c:1073
#4: ffff88803aaee1d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline]
#4: ffff88803aaee1d8 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x450 drivers/base/dd.c:1073
1 lock held by syz.4.2589/11122:
#0: ffff88802a9b6210 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline]
#0: ffff88802a9b6210 (&dev->mutex){....}-{4:4}, at: usbdev_open+0x151/0x790 drivers/usb/core/devio.c:1054
5 locks held by syz-executor/11609:
2 locks held by syz.1.4696/15556:
2 locks held by syz.0.4697/15554:
3 locks held by syz.3.4698/15557:
=============================================
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 07/16/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:122
nmi_trigger_cpumask_backtrace+0x17a/0x380 lib/nmi_backtrace.c:65
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+0xfd7/0x1030 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: 11609 Comm: syz-executor Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
RIP: 0010:check_wait_context kernel/locking/lockdep.c:4882 [inline]
RIP: 0010:__lock_acquire+0x579/0x2ce0 kernel/locking/lockdep.c:5187
Code: 85 c0 74 1c 83 3d 6a 4a 0e 0e 00 75 13 48 8d 3d bd 94 11 0e 48 c7 c6 b4 3b 9a 8d 67 48 0f b9 3a 90 31 c9 0f b6 81 c4 00 00 00 <84> c0 0f 84 77 ff ff ff 41 0f b6 f4 0f b6 d0 40 38 c6 0f 42 d6 80
RSP: 0000:ffffc900078270c8 EFLAGS: 00000006
RAX: 0000000000000004 RBX: ffff888036f72b78 RCX: ffffffff934d0ca8
RDX: 0000000000000004 RSI: 0000000000000005 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffffffff823666ea R09: 0000000000000000
R10: 0000000000000000 R11: ffffffff8e1c30c0 R12: 0000000000000004
R13: ffff888036f72c70 R14: ffff888036f71f00 R15: 0000000000000002
FS: 000055557ef7f500(0000) GS:ffff888125c41000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c26ec42 CR3: 000000005db5c000 CR4: 00000000003526f0
Call Trace:
lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868
rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
rcu_read_lock_sched include/linux/rcupdate.h:938 [inline]
pfn_valid+0xd6/0x480 include/linux/mmzone.h:2270
page_table_check_set+0x25/0x530 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:447 [inline]
__copy_present_ptes mm/memory.c:1118 [inline]
copy_present_ptes mm/memory.c:1197 [inline]
copy_pte_range mm/memory.c:1320 [inline]
copy_pmd_range+0x33b5/0x53e0 mm/memory.c:1408
copy_pud_range mm/memory.c:1445 [inline]
copy_p4d_range mm/memory.c:1469 [inline]
copy_page_range+0xb34/0x1160 mm/memory.c:1555
dup_mmap+0xf2d/0x1d40 mm/mmap.c:1840
dup_mm kernel/fork.c:1543 [inline]
copy_mm+0x11a/0x480 kernel/fork.c:1595
copy_process+0x1e46/0x4390 kernel/fork.c:2289
kernel_clone+0x2d2/0x8d0 kernel/fork.c:2748
__do_sys_clone kernel/fork.c:2889 [inline]
__se_sys_clone kernel/fork.c:2873 [inline]
__x64_sys_clone+0x1b6/0x230 kernel/fork.c:2873
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa6c63e6912
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:00007ffc7bccebe0 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007ffc7bccebe0 RCX: 00007fa6c63e6912
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 00007ffc7bcced6c R08: 0000000000000000 R09: 0000000000000001
R10: 000055557ef7f7d0 R11: 0000000000000246 R12: 0000000000000001
R13: 00000000000927c0 R14: 000000000007101d R15: 00007ffc7bccedc0