INFO: task syz.2.2007:16580 blocked for more than 143 seconds.
Not tainted 6.15.0-rc3-syzkaller-00342-g5bc1018675ec #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.2007 state:D stack:25656 pid:16580 tgid:16578 ppid:8115 task_flags:0x400140 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x16e2/0x4cd0 kernel/sched/core.c:6767
__schedule_loop kernel/sched/core.c:6845 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6860
bit_wait+0x11/0xd0 kernel/sched/wait_bit.c:237
__wait_on_bit+0xb9/0x310 kernel/sched/wait_bit.c:49
out_of_line_wait_on_bit+0x123/0x170 kernel/sched/wait_bit.c:64
wait_on_bit include/linux/wait_bit.h:77 [inline]
netfs_unbuffered_write_iter_locked+0x567/0x990 fs/netfs/direct_write.c:108
netfs_unbuffered_write_iter+0x4c4/0x660 fs/netfs/direct_write.c:195
do_iter_readv_writev+0x56e/0x7f0 fs/read_write.c:-1
vfs_writev+0x306/0x9a0 fs/read_write.c:1055
do_pwritev fs/read_write.c:1151 [inline]
__do_sys_pwritev2 fs/read_write.c:1209 [inline]
__se_sys_pwritev2+0x179/0x290 fs/read_write.c:1200
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f160958e969
RSP: 002b:00007f160a4cd038 EFLAGS: 00000246 ORIG_RAX: 0000000000000148
RAX: ffffffffffffffda RBX: 00007f16097b5fa0 RCX: 00007f160958e969
RDX: 0000000000000001 RSI: 0000200000000080 RDI: 0000000000000009
RBP: 00007f1609610ab1 R08: 0000000000000007 R09: 0000000000000004
R10: 0000000000000008 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f16097b5fa0 R15: 00007ffc94ff4638
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6764
2 locks held by pvrusb2-context/2334:
#0: ffff88806f2e8188 (&hdw->big_lock_mutex){+.+.}-{4:4}, at: pvr2_hdw_initialize+0xc6/0x3ac0 drivers/media/usb/pvrusb2/pvrusb2-hdw.c:2326
#1: ffffffff8dde1ad0 (umhelper_sem){++++}-{4:4}, at: usermodehelper_read_trylock+0xf0/0x2b0 kernel/umh.c:214
2 locks held by getty/5577:
#0: ffff8880304e60a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc900030062f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
3 locks held by kworker/1:5/5886:
#0: ffff88801a078d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88801a078d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319
#1: ffffc90004fb7c60 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc90004fb7c60 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319
#2: ffff88805e8d2240 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x26b/0x3180 drivers/net/netdevsim/fib.c:1490
3 locks held by kworker/1:10/6352:
#0: ffff88801a078d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88801a078d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319
#1: ffffc9000ebd7c60 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc9000ebd7c60 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319
#2: ffff88807bd53240 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x26b/0x3180 drivers/net/netdevsim/fib.c:1490
2 locks held by kworker/u8:19/6628:
#0: ffff88801a081148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88801a081148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319
#1: ffffc9001f817c60 ((work_completion)(&rreq->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc9001f817c60 ((work_completion)(&rreq->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319
4 locks held by udevd/9082:
#0: ffff888029171790 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xb7/0xe10 fs/seq_file.c:182
#1: ffff88805e120488 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x55/0x3c0 fs/kernfs/file.c:154
#2: ffff8880324605a8 (kn->active#19){++++}-{0:0}, at: kernfs_seq_start+0x75/0x3c0 fs/kernfs/file.c:155
#3: ffff88805ce89198 (&dev->mutex){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:927 [inline]
#3: ffff88805ce89198 (&dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142
6 locks held by kworker/0:2/14694:
#0: ffff888144690148 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff888144690148 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319
#1: ffffc90015f57c60 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc90015f57c60 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319
#2: ffff888027db4198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline]
#2: ffff888027db4198 (&dev->mutex){....}-{4:4}, at: hub_event+0x184/0x4a00 drivers/usb/core/hub.c:5859
#3: ffff88805ce89198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline]
#3: ffff88805ce89198 (&dev->mutex){....}-{4:4}, at: usb_disconnect+0xf8/0x910 drivers/usb/core/hub.c:2307
#4: ffff88807dd2f160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline]
#4: ffff88807dd2f160 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1094 [inline]
#4: ffff88807dd2f160 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xb6/0x7c0 drivers/base/dd.c:1292
#5: ffff88806f2e8188 (&hdw->big_lock_mutex){+.+.}-{4:4}, at: pvr2_hdw_disconnect+0x6d/0x500 drivers/media/usb/pvrusb2/pvrusb2-hdw.c:2710
4 locks held by kworker/u8:7/14770:
#0: ffff88801aef6148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88801aef6148 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319
#1: ffffc90015d8fc60 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc90015d8fc60 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319
#2: ffffffff8f2e6c90 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0x145/0xbd0 net/core/net_namespace.c:608
#3: ffffffff8df41338 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:304 [inline]
#3: ffffffff8df41338 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f4/0x730 kernel/rcu/tree_exp.h:998
2 locks held by syz.2.2007/16580:
#0: ffff88804f400420 (sb_writers#36){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3041 [inline]
#0: ffff88804f400420 (sb_writers#36){.+.+}-{0:0}, at: vfs_writev+0x274/0x9a0 fs/read_write.c:1053
#1: ffff888053ce9498 (&sb->s_type->i_mutex_key#42){++++}-{4:4}, at: netfs_start_io_direct+0x1ef/0x230 fs/netfs/locking.c:188
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc3-syzkaller-00342-g5bc1018675ec #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025
Call Trace:
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/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+0xfee/0x1030 kernel/hung_task.c:437
kthread+0x711/0x8a0 kernel/kthread.c:464
ret_from_fork+0x4e/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: 14770 Comm: kworker/u8:7 Not tainted 6.15.0-rc3-syzkaller-00342-g5bc1018675ec #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025
Workqueue: netns cleanup_net
RIP: 0010:get_data+0x43c/0x860 kernel/printk/printk_ringbuffer.c:1255
Code: 44 24 18 80 3c 18 00 74 08 4c 89 f7 e8 3d c9 7f 00 49 8b 1e 4c 8d 73 07 49 83 e6 f8 48 89 df 4c 89 f6 e8 87 d6 1d 00 4c 39 f3 <0f> 85 a2 00 00 00 4c 89 f8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff
RSP: 0018:ffffc90015d8ef40 EFLAGS: 00000246
RAX: ffffffff81a1eaa9 RBX: 00000000000ab128 RCX: ffff888024ea0000
RDX: 0000000000000000 RSI: 00000000000ab128 RDI: 00000000000ab128
RBP: 1ffff92002bb1e0b R08: ffffc90015d8f277 R09: 1ffff92002bb1e4e
R10: dffffc0000000000 R11: fffff52002bb1e4f R12: 0000000000000078
R13: ffffc90015d8f058 R14: 00000000000ab128 R15: ffffc90015d8f090
FS: 0000000000000000(0000) GS:ffff8881261cc000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fff49030048 CR3: 000000000dd36000 CR4: 0000000000350ef0
Call Trace:
copy_data kernel/printk/printk_ringbuffer.c:1827 [inline]
prb_read kernel/printk/printk_ringbuffer.c:1936 [inline]
_prb_read_valid+0x672/0xa90 kernel/printk/printk_ringbuffer.c:2113
prb_read_valid+0x3c/0x60 kernel/printk/printk_ringbuffer.c:2185
printk_get_next_message+0x15c/0x7b0 kernel/printk/printk.c:3005
console_emit_next_record kernel/printk/printk.c:3092 [inline]
console_flush_all+0x4ca/0xc40 kernel/printk/printk.c:3226
__console_flush_and_unlock kernel/printk/printk.c:3285 [inline]
console_unlock+0xc4/0x270 kernel/printk/printk.c:3325
vprintk_emit+0x5b7/0x7a0 kernel/printk/printk.c:2450
_printk+0xcf/0x120 kernel/printk/printk.c:2475
netdev_info+0x10a/0x160 net/core/dev.c:12458
netif_set_allmulti+0x1b8/0x380 net/core/dev.c:9245
dev_set_allmulti+0x12b/0x260 net/core/dev_api.c:289
nbp_delete_promisc net/bridge/br_if.c:252 [inline]
del_nbp+0xae/0xa60 net/bridge/br_if.c:340
br_dev_delete+0x6e/0x100 net/bridge/br_if.c:386
br_net_exit_batch_rtnl+0xfc/0x1a0 net/bridge/br.c:376
cleanup_net+0x667/0xbd0 net/core/net_namespace.c:647
process_one_work kernel/workqueue.c:3238 [inline]
process_scheduled_works+0xade/0x17a0 kernel/workqueue.c:3319
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400
kthread+0x711/0x8a0 kernel/kthread.c:464
ret_from_fork+0x4e/0x80 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245