INFO: task syz.4.20:6104 blocked for more than 143 seconds.
Not tainted 6.15.0-rc7-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.20 state:D
stack:27560 pid:6104 tgid:6104 ppid:5961 task_flags:0x400040 flags:0x00000004
Call Trace:
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x116f/0x5de0 kernel/sched/core.c:6767
__schedule_loop kernel/sched/core.c:6845 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:6860
schedule_timeout+0x257/0x290 kernel/time/sleep_timeout.c:75
do_wait_for_common kernel/sched/completion.c:95 [inline]
__wait_for_common+0x2ff/0x4e0 kernel/sched/completion.c:116
__flush_work+0x7d7/0xcc0 kernel/workqueue.c:4244
__cancel_work_sync+0x10c/0x130 kernel/workqueue.c:4364
uhid_dev_destroy drivers/hid/uhid.c:584 [inline]
uhid_char_release+0xc4/0x210 drivers/hid/uhid.c:662
__fput+0x3ff/0xb70 fs/file_table.c:465
task_work_run+0x150/0x240 kernel/task_work.c:227
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x260 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4ee898e969
RSP: 002b:00007fff0a1bab78 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 000000000004860e RCX: 00007f4ee898e969
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000001 R09: 000000020a1bae6f
R10: 00007f4ee8800000 R11: 0000000000000246 R12: 00007f4ee8bb5fac
R13: 00007f4ee8bb5fa0 R14: ffffffffffffffff R15: 0000000000000003
Showing all locks held in the system:
3 locks held by kworker/1:0/24:
1 lock held by khungtaskd/31:
#0: ffffffff8e3bfc00 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e3bfc00 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e3bfc00 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6764
3 locks held by kworker/1:1/81:
3 locks held by kworker/1:2/971:
4 locks held by kworker/u8:6/1108:
#0: ffff88801c2f3948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213
#1: ffffc90003befd18 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214
#2: ffffffff90112b50 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xc9/0xb30 net/core/net_namespace.c:608
#3: ffffffff8e3cb138 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x1a3/0x3c0 kernel/rcu/tree_exp.h:336
1 lock held by dhcpcd/5479:
#0: ffffffff901289e8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#0: ffffffff901289e8 (rtnl_mutex){+.+.}-{4:4}, at: devinet_ioctl+0x26d/0x1f50 net/ipv4/devinet.c:1121
2 locks held by getty/5576:
#0: ffff88814d0890a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc9000333b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222
3 locks held by kworker/1:6/6071:
3 locks held by kworker/u8:8/6179:
#0: ffff888031eb2148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213
#1: ffffc9000416fd18 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214
#2: ffffffff901289e8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#2: ffffffff901289e8 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x120/0x14e0 net/ipv6/addrconf.c:4198
8 locks held by kworker/1:8/6214:
4 locks held by syz-executor/6335:
#0: ffff8880362be420 (sb_writers#8){.+.+}-{0:0}, at: ksys_write+0x12a/0x240 fs/read_write.c:736
#1: ffff888021fab088 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x28f/0x510 fs/kernfs/file.c:325
#2: ffff888027e26a58 (kn->active#58){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x2b2/0x510 fs/kernfs/file.c:326
#3: ffffffff8f6caa28 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x4a0 drivers/net/netdevsim/bus.c:216
4 locks held by syz-executor/6337:
#0: ffff8880362be420 (sb_writers#8){.+.+}-{0:0}, at: ksys_write+0x12a/0x240 fs/read_write.c:736
#1:
ffff88805e4bac88
(
&of->mutex
){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x28f/0x510 fs/kernfs/file.c:325
#2: ffff888027e26a58 (kn->active#58){.+.+}-{0:0}
, at: kernfs_fop_write_iter+0x2b2/0x510 fs/kernfs/file.c:326
#3:
ffffffff8f6caa28
(
nsim_bus_dev_list_lock
){+.+.}-{4:4}
, at: del_device_store+0xd1/0x4a0 drivers/net/netdevsim/bus.c:216
7 locks held by syz-executor/6344:
#0:
ffff8880362be420
(
sb_writers
#8
){.+.+}-{0:0}, at: ksys_write+0x12a/0x240 fs/read_write.c:736
#1: ffff88805e7fb888 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x28f/0x510 fs/kernfs/file.c:325
#2: ffff888027e26968 (kn->active#59){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x2b2/0x510 fs/kernfs/file.c:326
#3: ffffffff8f6caa28 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: new_device_store+0x185/0x730 drivers/net/netdevsim/bus.c:166
#4: ffff888068ba50e8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline]
#4: ffff888068ba50e8 (&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4b0 drivers/base/dd.c:1004
#5: ffff888068ba7250 (&devlink->lock_key#14){+.+.}-{4:4}
, at: nsim_drv_probe+0xd4/0x1490 drivers/net/netdevsim/dev.c:1537
#6:
ffffffff901289e8
(
rtnl_mutex
){+.+.}-{4:4}
, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
, at: rtnl_net_dev_lock+0x146/0x360 net/core/dev.c:2089
4 locks held by syz-executor/6348:
#0: ffff8880362be420
(sb_writers#8){.+.+}-{0:0}, at: ksys_write+0x12a/0x240 fs/read_write.c:736
#1: ffff88805e7fa488 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x28f/0x510 fs/kernfs/file.c:325
#2: ffff888027e26a58 (kn->active#58){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x2b2/0x510 fs/kernfs/file.c:326
#3: ffffffff8f6caa28 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x4a0 drivers/net/netdevsim/bus.c:216
3 locks held by syz-executor/6350:
#0: ffffffff901289e8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#0: ffffffff901289e8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#0: ffffffff901289e8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x600/0x2000 net/core/rtnetlink.c:4064
#1: ffff888025144d30 (&dev_instance_lock_key#20){+.+.}-{4:4}, at: netdev_lock include/linux/netdevice.h:2751 [inline]
#1: ffff888025144d30 (&dev_instance_lock_key#20){+.+.}-{4:4}, at: netdev_lock_ops include/net/netdev_lock.h:42 [inline]
#1: ffff888025144d30 (&dev_instance_lock_key#20){+.+.}-{4:4}, at: netdev_lock_ops include/net/netdev_lock.h:39 [inline]
#1: ffff888025144d30 (&dev_instance_lock_key#20){+.+.}-{4:4}, at: do_setlink.constprop.0+0x2ec/0x44b0 net/core/rtnetlink.c:3051
#2: ffffffff8e3cb138 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x280/0x3c0 kernel/rcu/tree_exp.h:304
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc7-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:274 [inline]
watchdog+0xf70/0x12c0 kernel/hung_task.c:437
kthread+0x3c2/0x780 kernel/kthread.c:464
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 6071 Comm: kworker/1:6 Not tainted 6.15.0-rc7-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: events uhid_device_add_worker
RIP: 0010:io_serial_in+0x87/0xb0 drivers/tty/serial/8250/8250_port.c:410
Code: a8 6b fc 48 8d 7d 40 44 89 e1 48 b8 00 00 00 00 00 fc ff df 48 89 fa d3 e3 48 c1 ea 03 80 3c 02 00 75 1a 66 03 5d 40 89 da ec <5b> 0f b6 c0 5d 41 5c e9 7d 7b 20 06 e8 58 27 d1 fc eb a2 e8 e1 27
RSP: 0018:ffffc9000492f018 EFLAGS: 00000002
RAX: dffffc0000000000 RBX: 00000000000003fd RCX: 0000000000000000
RDX: 00000000000003fd RSI: ffffffff854f9d30 RDI: ffffffff9adfe5a0
RBP: ffffffff9adfe560 R08: 0000000000000001 R09: 000000000000001f
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000020 R14: fffffbfff35bfd06 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff888124ada000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055a1aa1c4300 CR3: 000000000e180000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
serial_in drivers/tty/serial/8250/8250.h:137 [inline]
serial_lsr_in drivers/tty/serial/8250/8250.h:159 [inline]
wait_for_lsr+0x13a/0x210 drivers/tty/serial/8250/8250_port.c:2098
fifo_wait_for_lsr drivers/tty/serial/8250/8250_port.c:3348 [inline]
serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3371 [inline]
serial8250_console_write+0xf83/0x1890 drivers/tty/serial/8250/8250_port.c:3456
console_emit_next_record kernel/printk/printk.c:3138 [inline]
console_flush_all+0x801/0xc60 kernel/printk/printk.c:3226
__console_flush_and_unlock kernel/printk/printk.c:3285 [inline]
console_unlock+0xd8/0x210 kernel/printk/printk.c:3325
vprintk_emit+0x418/0x6d0 kernel/printk/printk.c:2450
dev_vprintk_emit drivers/base/core.c:4917 [inline]
dev_printk_emit+0xfa/0x140 drivers/base/core.c:4928
__dev_printk+0xf5/0x270 drivers/base/core.c:4940
_dev_warn+0xe4/0x120 drivers/base/core.c:4984
hid_parser_main+0x7a4/0xd80 drivers/hid/hid-core.c:664
hid_open_report+0x459/0x830 drivers/hid/hid-core.c:1328
hid_parse include/linux/hid.h:1126 [inline]
hid_generic_probe+0x4d/0x90 drivers/hid/hid-generic.c:66
__hid_device_probe drivers/hid/hid-core.c:2717 [inline]
hid_device_probe+0x357/0x710 drivers/hid/hid-core.c:2754
call_driver_probe drivers/base/dd.c:579 [inline]
really_probe+0x23e/0xa90 drivers/base/dd.c:657
__driver_probe_device+0x1de/0x440 drivers/base/dd.c:799
driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:829
__device_attach_driver+0x1df/0x310 drivers/base/dd.c:957
bus_for_each_drv+0x156/0x1e0 drivers/base/bus.c:462
__device_attach+0x1e4/0x4b0 drivers/base/dd.c:1029
bus_probe_device+0x17f/0x1c0 drivers/base/bus.c:537
device_add+0x1148/0x1a70 drivers/base/core.c:3692
hid_add_device+0x373/0xa60 drivers/hid/hid-core.c:2900
uhid_device_add_worker+0x3e/0x110 drivers/hid/uhid.c:73
process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3238
process_scheduled_works kernel/workqueue.c:3319 [inline]
worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400
kthread+0x3c2/0x780 kernel/kthread.c:464
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245