[v5.15] INFO: task hung in dvb_usbv2_probe
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syzbot
Aug 15, 2026, 5:31:37 PM (2 days ago) Aug 15
to syzkaller...@googlegroups.com
Hello,
syzbot found the following issue on:
HEAD commit: aabd761612db Linux 5.15.215
git tree: linux-5.15.y
console output: https://syzkaller.appspot.com/x/log.txt?x=166dc279580000
kernel config: https://syzkaller.appspot.com/x/.config?x=f161cbc9aef65db0
dashboard link: https://syzkaller.appspot.com/bug?extid=f69cd2923581cd5ac6c1
compiler: Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/f636f56d3662/disk-aabd7616.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/f1a46620f40c/vmlinux-aabd7616.xz
kernel image: https://storage.googleapis.com/syzbot-assets/9b78bb48b022/bzImage-aabd7616.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+f69cd2...@syzkaller.appspotmail.com
INFO: task kworker/1:16:6686 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/1:16 state:D stack:22832 pid: 6686 ppid: 2 flags:0x00004000
Workqueue: usb_hub_wq hub_event
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11c3/0x4350 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
schedule_timeout+0xbd/0x2d0 kernel/time/timer.c:2093
do_wait_for_common+0x295/0x460 kernel/sched/completion.c:85
__wait_for_common kernel/sched/completion.c:106 [inline]
wait_for_common kernel/sched/completion.c:117 [inline]
wait_for_completion+0x48/0x60 kernel/sched/completion.c:138
i2c_del_adapter+0x2c9/0x430 drivers/i2c/i2c-core-base.c:1840
dvb_usbv2_probe+0x4cd/0x3c80 drivers/media/usb/dvb-usb-v2/dvb_usb_core.c:993
usb_probe_interface+0x5be/0xae0 drivers/usb/core/driver.c:396
call_driver_probe drivers/base/dd.c:-1 [inline]
really_probe+0x276/0xc70 drivers/base/dd.c:595
__driver_probe_device+0x1f5/0x390 drivers/base/dd.c:775
driver_probe_device+0x4f/0x420 drivers/base/dd.c:805
__device_attach_driver+0x2b0/0x500 drivers/base/dd.c:927
bus_for_each_drv+0x184/0x210 drivers/base/bus.c:429
__device_attach+0x2a7/0x480 drivers/base/dd.c:999
bus_probe_device+0xba/0x1d0 drivers/base/bus.c:489
device_add+0xbcf/0x1050 drivers/base/core.c:3427
usb_set_configuration+0x19d5/0x2030 drivers/usb/core/message.c:2223
usb_generic_driver_probe+0x89/0x150 drivers/usb/core/generic.c:238
usb_probe_device+0x126/0x250 drivers/usb/core/driver.c:293
call_driver_probe drivers/base/dd.c:-1 [inline]
really_probe+0x276/0xc70 drivers/base/dd.c:595
__driver_probe_device+0x1f5/0x390 drivers/base/dd.c:775
driver_probe_device+0x4f/0x420 drivers/base/dd.c:805
__device_attach_driver+0x2b0/0x500 drivers/base/dd.c:927
bus_for_each_drv+0x184/0x210 drivers/base/bus.c:429
__device_attach+0x2a7/0x480 drivers/base/dd.c:999
bus_probe_device+0xba/0x1d0 drivers/base/bus.c:489
device_add+0xbcf/0x1050 drivers/base/core.c:3427
usb_new_device+0x9f6/0x15d0 drivers/usb/core/hub.c:2632
hub_port_connect drivers/usb/core/hub.c:5497 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5637 [inline]
port_event drivers/usb/core/hub.c:5799 [inline]
hub_event+0x2b8d/0x5260 drivers/usb/core/hub.c:5881
process_one_work+0x867/0xff0 kernel/workqueue.c:2310
worker_thread+0xad7/0x12a0 kernel/workqueue.c:2457
kthread+0x42e/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
</TASK>
INFO: task udevd:8833 blocked for more than 145 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:udevd state:D stack:25264 pid: 8833 ppid: 3558 flags:0x00004002
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11c3/0x4350 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+0xdf5/0x2400 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:809 [inline]
uevent_show+0x16c/0x320 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+0x460/0xc50 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+0x75e/0xd50 fs/read_write.c:485
ksys_read+0x153/0x260 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: 0033:0x7f7745308407
RSP: 002b:00007ffcc2b20120 EFLAGS: 00000202 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 00007f774521a880 RCX: 00007f7745308407
RDX: 0000000000001000 RSI: 000055d6b19268a0 RDI: 0000000000000008
RBP: 00007f7745450ff0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 000000000000000a
R13: 00007f7745450ea0 R14: 0000000000000000 R15: 000055d6b1921010
</TASK>
INFO: task syz.6.1259:9770 blocked for more than 145 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.6.1259 state:D stack:26448 pid: 9770 ppid: 6542 flags:0x00004004
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11c3/0x4350 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+0xdf5/0x2400 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:809 [inline]
usbdev_do_ioctl drivers/usb/core/devio.c:2597 [inline]
usbdev_ioctl+0x146/0x1f20 drivers/usb/core/devio.c:2805
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: 0033:0x7fa2ddec90d9
RSP: 002b:00007fa2dc121028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fa2de150fa0 RCX: 00007fa2ddec90d9
RDX: 0000200000000000 RSI: 000000008038550a RDI: 0000000000000005
RBP: 00007fa2ddf60024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa2de151038 R14: 00007fa2de150fa0 R15: 00007ffe2b553bc8
</TASK>
INFO: task syz.6.1259:9771 blocked for more than 146 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.6.1259 state:D stack:27888 pid: 9771 ppid: 6542 flags:0x00004004
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11c3/0x4350 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+0xdf5/0x2400 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:809 [inline]
usbdev_do_ioctl drivers/usb/core/devio.c:2597 [inline]
usbdev_ioctl+0x146/0x1f20 drivers/usb/core/devio.c:2805
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: 0033:0x7fa2ddec90d9
RSP: 002b:00007fa2dc100028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fa2de151090 RCX: 00007fa2ddec90d9
RDX: 0000200000000000 RSI: 000000008038550a RDI: 0000000000000005
RBP: 00007fa2ddf60024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa2de151128 R14: 00007fa2de151090 R15: 00007ffe2b553bc8
</TASK>
Showing all locks held in the system:
3 locks held by kworker/1:1/23:
#0: ffff88802b046d38 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x75c/0xff0 kernel/workqueue.c:-1
#1: ffffc90000ddfd00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x79e/0xff0 kernel/workqueue.c:2285
#2: ffffffff8d44d488 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xc4/0x1530 net/ipv6/addrconf.c:4120
1 lock held by khungtaskd/27:
#0: ffffffff8c31ef60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
2 locks held by dhcpcd/3850:
#0: ffff88801eb14690 (nlk_cb_mutex-ROUTE){+.+.}-{3:3}, at: __netlink_dump_start+0xf5/0x720 net/netlink/af_netlink.c:2363
#1: ffffffff8d44d488 (rtnl_mutex){+.+.}-{3:3}, at: netlink_dump+0x70a/0xdd0 net/netlink/af_netlink.c:2290
2 locks held by getty/3939:
#0: ffff88814cad9098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
#1: ffffc90002cf62e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x594/0x1a50 drivers/tty/n_tty.c:2158
3 locks held by kworker/u4:9/4400:
#0: ffff888016dcd938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x75c/0xff0 kernel/workqueue.c:-1
#1: ffffc9000320fd00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x79e/0xff0 kernel/workqueue.c:2285
#2: ffffffff8d441550 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x148/0xba0 net/core/net_namespace.c:589
2 locks held by kworker/1:10/6674:
#0: ffff888016c72138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x75c/0xff0 kernel/workqueue.c:-1
#1: ffffc9000335fd00 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x79e/0xff0 kernel/workqueue.c:2285
3 locks held by kworker/1:14/6681:
#0: ffff888016c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x75c/0xff0 kernel/workqueue.c:-1
#1: ffffc9000348fd00 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x79e/0xff0 kernel/workqueue.c:2285
#2: ffffffff8c3239e8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:322 [inline]
#2: ffffffff8c3239e8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3a5/0x750 kernel/rcu/tree_exp.h:845
5 locks held by kworker/1:16/6686:
#0: ffff888142bd3538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x75c/0xff0 kernel/workqueue.c:-1
#1: ffffc9000349fd00 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x79e/0xff0 kernel/workqueue.c:2285
#2: ffff888024442220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:809 [inline]
#2: ffff888024442220 (&dev->mutex){....}-{3:3}, at: hub_event+0x178/0x5260 drivers/usb/core/hub.c:5827
#3: ffff88802b2fd220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:809 [inline]
#3: ffff88802b2fd220 (&dev->mutex){....}-{3:3}, at: __device_attach+0x85/0x480 drivers/base/dd.c:974
#4: ffff88801fc231a8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:809 [inline]
#4: ffff88801fc231a8 (&dev->mutex){....}-{3:3}, at: __device_attach+0x85/0x480 drivers/base/dd.c:974
4 locks held by udevd/8833:
#0: ffff8880681951c8 (&p->lock){+.+.}-{3:3}, at: seq_read_iter+0x9d/0xc50 fs/seq_file.c:182
#1: ffff88805ee9d888 (&of->mutex){+.+.}-{3:3}, at: kernfs_seq_start+0x55/0x3c0 fs/kernfs/file.c:112
#2: ffff888073bb90f0 (kn->active#32){++++}-{0:0}, at: kernfs_seq_start+0x75/0x3c0 fs/kernfs/file.c:113
#3: ffff88802b2fd220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:809 [inline]
#3: ffff88802b2fd220 (&dev->mutex){....}-{3:3}, at: uevent_show+0x16c/0x320 drivers/base/core.c:2408
1 lock held by syz.6.1259/9770:
#0: ffff888024442220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:809 [inline]
#0: ffff888024442220 (&dev->mutex){....}-{3:3}, at: usbdev_do_ioctl drivers/usb/core/devio.c:2597 [inline]
#0: ffff888024442220 (&dev->mutex){....}-{3:3}, at: usbdev_ioctl+0x146/0x1f20 drivers/usb/core/devio.c:2805
1 lock held by syz.6.1259/9771:
#0: ffff888024442220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:809 [inline]
#0: ffff888024442220 (&dev->mutex){....}-{3:3}, at: usbdev_do_ioctl drivers/usb/core/devio.c:2597 [inline]
#0: ffff888024442220 (&dev->mutex){....}-{3:3}, at: usbdev_ioctl+0x146/0x1f20 drivers/usb/core/devio.c:2805
1 lock held by syz.9.1658/11679:
#0: ffff888024442220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:809 [inline]
#0: ffff888024442220 (&dev->mutex){....}-{3:3}, at: usbdev_open+0x14e/0x7a0 drivers/usb/core/devio.c:1040
1 lock held by syz.1.1765/12260:
#0: ffff888024442220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:809 [inline]
#0: ffff888024442220 (&dev->mutex){....}-{3:3}, at: usbdev_open+0x14e/0x7a0 drivers/usb/core/devio.c:1040
1 lock held by syz-executor/12447:
#0: ffffffff8d44d488 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
#0: ffffffff8d44d488 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x79f/0xf10 net/core/rtnetlink.c:5695
2 locks held by syz-executor/12586:
#0: ffffffff8d44d488 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
#0: ffffffff8d44d488 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x79f/0xf10 net/core/rtnetlink.c:5695
#1: ffffffff8c3239e8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:322 [inline]
#1: ffffffff8c3239e8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3a5/0x750 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 07/24/2026
Call Trace:
<TASK>
dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
nmi_cpu_backtrace+0x3a2/0x3d0 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+0xe1b/0xe60 kernel/hung_task.c:369
kthread+0x42e/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
</TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 6681 Comm: kworker/1:14 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Workqueue: 0x0 (wg-kex-wg2)
RIP: 0010:dequeue_task_fair+0x0/0x1030 kernel/sched/fair.c:5913
Code: 49 89 1e e9 b1 f7 ff ff 44 89 e1 80 e1 07 80 c1 03 38 c1 0f 8c b8 fd ff ff 4c 89 e7 e8 b9 be 67 00 e9 ab fd ff ff 0f 1f 40 00 <55> 41 57 41 56 41 55 41 54 53 48 81 ec 88 00 00 00 89 54 24 10 49
RSP: 0018:ffffc9000348fbb8 EFLAGS: 00000046
RAX: 1ffffffff17c6ea3 RBX: ffffffff8be37518 RCX: 0000000000000001
RDX: 0000000000000009 RSI: ffff88801df83b80 RDI: ffff8880b913a340
RBP: ffffc9000348fd88 R08: ffffffff8f103048 R09: ffffffff8f103058
R10: ffffffff8f103050 R11: ffffffff8f103043 R12: dffffc0000000000
R13: ffffc9000348fd20 R14: ffff88801df83b80 R15: ffff88801df83b80
FS: 0000000000000000(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f8b7526b848 CR3: 0000000023c88000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
dequeue_task kernel/sched/core.c:2016 [inline]
deactivate_task kernel/sched/core.c:2033 [inline]
__schedule+0x6cf/0x4350 kernel/sched/core.c:6349
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
worker_thread+0xf90/0x12a0 kernel/workqueue.c:2478
kthread+0x42e/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
</TASK>
---
This report is generated by a bot. It may contain errors.
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If the report is already addressed, let syzbot know by replying with:
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If the report is a duplicate of another one, reply with:
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If you want to undo deduplication, reply with:
#syz undup
syzbot found the following issue on:
HEAD commit: aabd761612db Linux 5.15.215
git tree: linux-5.15.y
console output: https://syzkaller.appspot.com/x/log.txt?x=166dc279580000
kernel config: https://syzkaller.appspot.com/x/.config?x=f161cbc9aef65db0
dashboard link: https://syzkaller.appspot.com/bug?extid=f69cd2923581cd5ac6c1
compiler: Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/f636f56d3662/disk-aabd7616.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/f1a46620f40c/vmlinux-aabd7616.xz
kernel image: https://storage.googleapis.com/syzbot-assets/9b78bb48b022/bzImage-aabd7616.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+f69cd2...@syzkaller.appspotmail.com
INFO: task kworker/1:16:6686 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/1:16 state:D stack:22832 pid: 6686 ppid: 2 flags:0x00004000
Workqueue: usb_hub_wq hub_event
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11c3/0x4350 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
schedule_timeout+0xbd/0x2d0 kernel/time/timer.c:2093
do_wait_for_common+0x295/0x460 kernel/sched/completion.c:85
__wait_for_common kernel/sched/completion.c:106 [inline]
wait_for_common kernel/sched/completion.c:117 [inline]
wait_for_completion+0x48/0x60 kernel/sched/completion.c:138
i2c_del_adapter+0x2c9/0x430 drivers/i2c/i2c-core-base.c:1840
dvb_usbv2_probe+0x4cd/0x3c80 drivers/media/usb/dvb-usb-v2/dvb_usb_core.c:993
usb_probe_interface+0x5be/0xae0 drivers/usb/core/driver.c:396
call_driver_probe drivers/base/dd.c:-1 [inline]
really_probe+0x276/0xc70 drivers/base/dd.c:595
__driver_probe_device+0x1f5/0x390 drivers/base/dd.c:775
driver_probe_device+0x4f/0x420 drivers/base/dd.c:805
__device_attach_driver+0x2b0/0x500 drivers/base/dd.c:927
bus_for_each_drv+0x184/0x210 drivers/base/bus.c:429
__device_attach+0x2a7/0x480 drivers/base/dd.c:999
bus_probe_device+0xba/0x1d0 drivers/base/bus.c:489
device_add+0xbcf/0x1050 drivers/base/core.c:3427
usb_set_configuration+0x19d5/0x2030 drivers/usb/core/message.c:2223
usb_generic_driver_probe+0x89/0x150 drivers/usb/core/generic.c:238
usb_probe_device+0x126/0x250 drivers/usb/core/driver.c:293
call_driver_probe drivers/base/dd.c:-1 [inline]
really_probe+0x276/0xc70 drivers/base/dd.c:595
__driver_probe_device+0x1f5/0x390 drivers/base/dd.c:775
driver_probe_device+0x4f/0x420 drivers/base/dd.c:805
__device_attach_driver+0x2b0/0x500 drivers/base/dd.c:927
bus_for_each_drv+0x184/0x210 drivers/base/bus.c:429
__device_attach+0x2a7/0x480 drivers/base/dd.c:999
bus_probe_device+0xba/0x1d0 drivers/base/bus.c:489
device_add+0xbcf/0x1050 drivers/base/core.c:3427
usb_new_device+0x9f6/0x15d0 drivers/usb/core/hub.c:2632
hub_port_connect drivers/usb/core/hub.c:5497 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5637 [inline]
port_event drivers/usb/core/hub.c:5799 [inline]
hub_event+0x2b8d/0x5260 drivers/usb/core/hub.c:5881
process_one_work+0x867/0xff0 kernel/workqueue.c:2310
worker_thread+0xad7/0x12a0 kernel/workqueue.c:2457
kthread+0x42e/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
</TASK>
INFO: task udevd:8833 blocked for more than 145 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:udevd state:D stack:25264 pid: 8833 ppid: 3558 flags:0x00004002
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11c3/0x4350 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+0xdf5/0x2400 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:809 [inline]
uevent_show+0x16c/0x320 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+0x460/0xc50 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+0x75e/0xd50 fs/read_write.c:485
ksys_read+0x153/0x260 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: 0033:0x7f7745308407
RSP: 002b:00007ffcc2b20120 EFLAGS: 00000202 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 00007f774521a880 RCX: 00007f7745308407
RDX: 0000000000001000 RSI: 000055d6b19268a0 RDI: 0000000000000008
RBP: 00007f7745450ff0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 000000000000000a
R13: 00007f7745450ea0 R14: 0000000000000000 R15: 000055d6b1921010
</TASK>
INFO: task syz.6.1259:9770 blocked for more than 145 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.6.1259 state:D stack:26448 pid: 9770 ppid: 6542 flags:0x00004004
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11c3/0x4350 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+0xdf5/0x2400 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:809 [inline]
usbdev_do_ioctl drivers/usb/core/devio.c:2597 [inline]
usbdev_ioctl+0x146/0x1f20 drivers/usb/core/devio.c:2805
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: 0033:0x7fa2ddec90d9
RSP: 002b:00007fa2dc121028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fa2de150fa0 RCX: 00007fa2ddec90d9
RDX: 0000200000000000 RSI: 000000008038550a RDI: 0000000000000005
RBP: 00007fa2ddf60024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa2de151038 R14: 00007fa2de150fa0 R15: 00007ffe2b553bc8
</TASK>
INFO: task syz.6.1259:9771 blocked for more than 146 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.6.1259 state:D stack:27888 pid: 9771 ppid: 6542 flags:0x00004004
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11c3/0x4350 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+0xdf5/0x2400 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:809 [inline]
usbdev_do_ioctl drivers/usb/core/devio.c:2597 [inline]
usbdev_ioctl+0x146/0x1f20 drivers/usb/core/devio.c:2805
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: 0033:0x7fa2ddec90d9
RSP: 002b:00007fa2dc100028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fa2de151090 RCX: 00007fa2ddec90d9
RDX: 0000200000000000 RSI: 000000008038550a RDI: 0000000000000005
RBP: 00007fa2ddf60024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa2de151128 R14: 00007fa2de151090 R15: 00007ffe2b553bc8
</TASK>
Showing all locks held in the system:
3 locks held by kworker/1:1/23:
#0: ffff88802b046d38 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x75c/0xff0 kernel/workqueue.c:-1
#1: ffffc90000ddfd00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x79e/0xff0 kernel/workqueue.c:2285
#2: ffffffff8d44d488 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xc4/0x1530 net/ipv6/addrconf.c:4120
1 lock held by khungtaskd/27:
#0: ffffffff8c31ef60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
2 locks held by dhcpcd/3850:
#0: ffff88801eb14690 (nlk_cb_mutex-ROUTE){+.+.}-{3:3}, at: __netlink_dump_start+0xf5/0x720 net/netlink/af_netlink.c:2363
#1: ffffffff8d44d488 (rtnl_mutex){+.+.}-{3:3}, at: netlink_dump+0x70a/0xdd0 net/netlink/af_netlink.c:2290
2 locks held by getty/3939:
#0: ffff88814cad9098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
#1: ffffc90002cf62e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x594/0x1a50 drivers/tty/n_tty.c:2158
3 locks held by kworker/u4:9/4400:
#0: ffff888016dcd938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x75c/0xff0 kernel/workqueue.c:-1
#1: ffffc9000320fd00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x79e/0xff0 kernel/workqueue.c:2285
#2: ffffffff8d441550 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x148/0xba0 net/core/net_namespace.c:589
2 locks held by kworker/1:10/6674:
#0: ffff888016c72138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x75c/0xff0 kernel/workqueue.c:-1
#1: ffffc9000335fd00 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x79e/0xff0 kernel/workqueue.c:2285
3 locks held by kworker/1:14/6681:
#0: ffff888016c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x75c/0xff0 kernel/workqueue.c:-1
#1: ffffc9000348fd00 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x79e/0xff0 kernel/workqueue.c:2285
#2: ffffffff8c3239e8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:322 [inline]
#2: ffffffff8c3239e8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3a5/0x750 kernel/rcu/tree_exp.h:845
5 locks held by kworker/1:16/6686:
#0: ffff888142bd3538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x75c/0xff0 kernel/workqueue.c:-1
#1: ffffc9000349fd00 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x79e/0xff0 kernel/workqueue.c:2285
#2: ffff888024442220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:809 [inline]
#2: ffff888024442220 (&dev->mutex){....}-{3:3}, at: hub_event+0x178/0x5260 drivers/usb/core/hub.c:5827
#3: ffff88802b2fd220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:809 [inline]
#3: ffff88802b2fd220 (&dev->mutex){....}-{3:3}, at: __device_attach+0x85/0x480 drivers/base/dd.c:974
#4: ffff88801fc231a8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:809 [inline]
#4: ffff88801fc231a8 (&dev->mutex){....}-{3:3}, at: __device_attach+0x85/0x480 drivers/base/dd.c:974
4 locks held by udevd/8833:
#0: ffff8880681951c8 (&p->lock){+.+.}-{3:3}, at: seq_read_iter+0x9d/0xc50 fs/seq_file.c:182
#1: ffff88805ee9d888 (&of->mutex){+.+.}-{3:3}, at: kernfs_seq_start+0x55/0x3c0 fs/kernfs/file.c:112
#2: ffff888073bb90f0 (kn->active#32){++++}-{0:0}, at: kernfs_seq_start+0x75/0x3c0 fs/kernfs/file.c:113
#3: ffff88802b2fd220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:809 [inline]
#3: ffff88802b2fd220 (&dev->mutex){....}-{3:3}, at: uevent_show+0x16c/0x320 drivers/base/core.c:2408
1 lock held by syz.6.1259/9770:
#0: ffff888024442220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:809 [inline]
#0: ffff888024442220 (&dev->mutex){....}-{3:3}, at: usbdev_do_ioctl drivers/usb/core/devio.c:2597 [inline]
#0: ffff888024442220 (&dev->mutex){....}-{3:3}, at: usbdev_ioctl+0x146/0x1f20 drivers/usb/core/devio.c:2805
1 lock held by syz.6.1259/9771:
#0: ffff888024442220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:809 [inline]
#0: ffff888024442220 (&dev->mutex){....}-{3:3}, at: usbdev_do_ioctl drivers/usb/core/devio.c:2597 [inline]
#0: ffff888024442220 (&dev->mutex){....}-{3:3}, at: usbdev_ioctl+0x146/0x1f20 drivers/usb/core/devio.c:2805
1 lock held by syz.9.1658/11679:
#0: ffff888024442220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:809 [inline]
#0: ffff888024442220 (&dev->mutex){....}-{3:3}, at: usbdev_open+0x14e/0x7a0 drivers/usb/core/devio.c:1040
1 lock held by syz.1.1765/12260:
#0: ffff888024442220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:809 [inline]
#0: ffff888024442220 (&dev->mutex){....}-{3:3}, at: usbdev_open+0x14e/0x7a0 drivers/usb/core/devio.c:1040
1 lock held by syz-executor/12447:
#0: ffffffff8d44d488 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
#0: ffffffff8d44d488 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x79f/0xf10 net/core/rtnetlink.c:5695
2 locks held by syz-executor/12586:
#0: ffffffff8d44d488 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
#0: ffffffff8d44d488 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x79f/0xf10 net/core/rtnetlink.c:5695
#1: ffffffff8c3239e8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:322 [inline]
#1: ffffffff8c3239e8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3a5/0x750 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 07/24/2026
Call Trace:
<TASK>
dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
nmi_cpu_backtrace+0x3a2/0x3d0 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+0xe1b/0xe60 kernel/hung_task.c:369
kthread+0x42e/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
</TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 6681 Comm: kworker/1:14 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Workqueue: 0x0 (wg-kex-wg2)
RIP: 0010:dequeue_task_fair+0x0/0x1030 kernel/sched/fair.c:5913
Code: 49 89 1e e9 b1 f7 ff ff 44 89 e1 80 e1 07 80 c1 03 38 c1 0f 8c b8 fd ff ff 4c 89 e7 e8 b9 be 67 00 e9 ab fd ff ff 0f 1f 40 00 <55> 41 57 41 56 41 55 41 54 53 48 81 ec 88 00 00 00 89 54 24 10 49
RSP: 0018:ffffc9000348fbb8 EFLAGS: 00000046
RAX: 1ffffffff17c6ea3 RBX: ffffffff8be37518 RCX: 0000000000000001
RDX: 0000000000000009 RSI: ffff88801df83b80 RDI: ffff8880b913a340
RBP: ffffc9000348fd88 R08: ffffffff8f103048 R09: ffffffff8f103058
R10: ffffffff8f103050 R11: ffffffff8f103043 R12: dffffc0000000000
R13: ffffc9000348fd20 R14: ffff88801df83b80 R15: ffff88801df83b80
FS: 0000000000000000(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f8b7526b848 CR3: 0000000023c88000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
dequeue_task kernel/sched/core.c:2016 [inline]
deactivate_task kernel/sched/core.c:2033 [inline]
__schedule+0x6cf/0x4350 kernel/sched/core.c:6349
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
worker_thread+0xf90/0x12a0 kernel/workqueue.c:2478
kthread+0x42e/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
</TASK>
---
This report is generated by a bot. It may contain errors.
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