INFO: task syz.5.1731:15363 blocked for more than 143 seconds.
      Not tainted 6.14.0-rc7-syzkaller-00196-g88d324e69ea9 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.1731      state:D stack:26416 pid:15363 tgid:15328 ppid:13783  task_flags:0x400140 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5378 [inline]
 __schedule+0xf43/0x5890 kernel/sched/core.c:6765
 __schedule_loop kernel/sched/core.c:6842 [inline]
 schedule+0xe7/0x350 kernel/sched/core.c:6857
 schedule_timeout+0x244/0x280 kernel/time/sleep_timeout.c:75
 do_wait_for_common kernel/sched/completion.c:95 [inline]
 __wait_for_common+0x3e1/0x600 kernel/sched/completion.c:116
 __flush_workqueue+0x3dc/0x1260 kernel/workqueue.c:4000
 nbd_start_device_ioctl drivers/block/nbd.c:1541 [inline]
 __nbd_ioctl drivers/block/nbd.c:1602 [inline]
 nbd_ioctl+0x308/0xd60 drivers/block/nbd.c:1642
 blkdev_ioctl+0x276/0x6d0 block/ioctl.c:693
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:906 [inline]
 __se_sys_ioctl fs/ioctl.c:892 [inline]
 __x64_sys_ioctl+0x190/0x200 fs/ioctl.c:892
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd23b78d169
RSP: 002b:00007fd23c5d4038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fd23b9a6160 RCX: 00007fd23b78d169
RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000006
RBP: 00007fd23b80e2a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fd23b9a6160 R15: 00007fffba3fd518
 </TASK>

Showing all locks held in the system:
5 locks held by kworker/0:0/9:
1 lock held by khungtaskd/31:
 #0: ffffffff8e1bd140 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
 #0: ffffffff8e1bd140 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #0: ffffffff8e1bd140 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x7f/0x390 kernel/locking/lockdep.c:6746
5 locks held by kworker/0:2/1200:
3 locks held by kworker/u8:8/3547:
 #0: ffff8880b863ec18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:606 [inline]
 #0: ffff8880b863ec18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x7e/0x130 kernel/sched/core.c:591
 #1: ffff8880b8628a88 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x2c1/0x8e0 kernel/sched/psi.c:987
 #2: ffff888031af56d8 (key#17){+...}-{3:3}, at: spin_lock_bh include/linux/spinlock.h:356 [inline]
 #2: ffff888031af56d8 (key#17){+...}-{3:3}, at: batadv_nc_purge_paths+0xca/0x390 net/batman-adv/network-coding.c:442
2 locks held by getty/5580:
 #0: 
ffff8880320210a0
 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
 #1: ffffc90002fde2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0xfba/0x1480 drivers/tty/n_tty.c:2211
2 locks held by kworker/u9:7/5836:
 #0: ffff888025cbe148 ((wq_completion)nbd5-recv){+.+.}-{0:0}, at: process_one_work+0x1293/0x1ba0 kernel/workqueue.c:3213
 #1: ffffc9000408fd18 ((work_completion)(&args->work)){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3214
5 locks held by kworker/1:4/5872:
 #0: ffff888144ac8948 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x1293/0x1ba0 kernel/workqueue.c:3213
 #1: ffffc900040ffd18 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3214
 #2: ffff888029267190 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1030 [inline]
 #2: ffff888029267190 (&dev->mutex){....}-{4:4}, at: hub_event+0x1c1/0x4e10 drivers/usb/core/hub.c:5861
 #3: ffff88806583f190 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1030 [inline]
 #3: ffff88806583f190 (&dev->mutex){....}-{4:4}, at: __device_attach+0x7f/0x4b0 drivers/base/dd.c:1005
 #4: ffff88807ed22160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1030 [inline]
 #4: ffff88807ed22160 (&dev->mutex){....}-{4:4}, at: __device_attach+0x7f/0x4b0 drivers/base/dd.c:1005
3 locks held by syz.6.2289/18791:
 #0: ffff888031db0e08 (&sb->s_type->i_mutex_key#10){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:877 [inline]
 #0: ffff888031db0e08 (&sb->s_type->i_mutex_key#10){+.+.}-{4:4}, at: __sock_release+0x86/0x270 net/socket.c:646
 #1: ffff88806bff0258 (sk_lock-AF_CAN){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1624 [inline]
 #1: ffff88806bff0258 (sk_lock-AF_CAN){+.+.}-{0:0}, at: isotp_release+0x449/0xa50 net/can/isotp.c:1202
 #2: ffffffff8e1c85b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x282/0x3b0 kernel/rcu/tree_exp.h:302
2 locks held by dhcpcd/18794:
 #0: ffff88805215e258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1624 [inline]
 #0: ffff88805215e258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x2c/0xf60 net/packet/af_packet.c:3253
 #1: ffffffff8e1c85b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x1a4/0x3b0 kernel/rcu/tree_exp.h:334
1 lock held by dhcpcd/18795:
 #0: ffff888052158258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1624 [inline]
 #0: ffff888052158258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x2c/0xf60 net/packet/af_packet.c:3253
1 lock held by sed/18799:
 #0: ffff8880b863ec18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:606 [inline]
 #0: ffff8880b863ec18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x7e/0x130 kernel/sched/core.c:591

=============================================

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.14.0-rc7-syzkaller-00196-g88d324e69ea9 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
 <TASK>
 __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:162 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:236 [inline]
 watchdog+0xf62/0x12b0 kernel/hung_task.c:399
 kthread+0x3af/0x750 kernel/kthread.c:464
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 9 Comm: kworker/0:0 Not tainted 6.14.0-rc7-syzkaller-00196-g88d324e69ea9 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Workqueue: usb_hub_wq hub_event
RIP: 0010:__sanitizer_cov_trace_pc+0x66/0x70 kernel/kcov.c:235
Code: 82 08 16 00 00 83 f8 02 75 20 48 8b 8a 10 16 00 00 8b 92 0c 16 00 00 48 8b 01 48 83 c0 01 48 39 d0 73 07 48 89 01 48 89 34 c1 <c3> cc cc cc cc 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90000007da8 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 000000002377c770 RCX: ffffffff816ad368
RDX: ffff88801c2f4880 RSI: ffffffff816ad377 RDI: 0000000000000001
RBP: 000000000000002e R08: 0000000000000001 R09: 000000000000003f
R10: 000000000000002e R11: 0000000000000005 R12: 0000000000000000
R13: ffff88805b8c7300 R14: 0000000000000000 R15: 0000000000000003
FS:  0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000557ac3d91ca8 CR3: 000000004faac000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 phys_addr_valid arch/x86/mm/physaddr.h:7 [inline]
 __phys_addr+0xa7/0x150 arch/x86/mm/physaddr.c:28
 virt_to_folio include/linux/mm.h:1295 [inline]
 virt_to_slab mm/slab.h:211 [inline]
 slab_free_after_rcu_debug+0x28/0x340 mm/slub.c:4643
 rcu_do_batch kernel/rcu/tree.c:2546 [inline]
 rcu_core+0x79d/0x14d0 kernel/rcu/tree.c:2802
 handle_softirqs+0x213/0x8f0 kernel/softirq.c:561
 __do_softirq kernel/softirq.c:595 [inline]
 invoke_softirq kernel/softirq.c:435 [inline]
 __irq_exit_rcu+0x109/0x170 kernel/softirq.c:662
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:678
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
 sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1049
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:console_trylock_spinning kernel/printk/printk.c:2061 [inline]
RIP: 0010:vprintk_emit+0x621/0x6f0 kernel/printk/printk.c:2431
Code: 85 ed 0f 85 81 00 00 00 e8 ec 34 20 00 9c 41 5c 41 81 e4 00 02 00 00 31 ff 4c 89 e6 e8 08 30 20 00 4d 85 e4 0f 85 8d 00 00 00 <e8> ca 34 20 00 45 31 c9 41 b8 01 00 00 00 31 c9 48 8d 05 00 00 00
RSP: 0018:ffffc900000e7648 EFLAGS: 00000283
RAX: 00000000000ea56d RBX: 000000000000002c RCX: ffffc9001ddd6000
RDX: 0000000000100000 RSI: ffffffff8199bc28 RDI: 0000000000000007
RBP: 1ffff9200001cecb R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000005 R12: 0000000000000000
R13: 0000000000000200 R14: ffff888020a88000 R15: ffffc900000e7710
 dev_vprintk_emit drivers/base/core.c:4891 [inline]
 dev_printk_emit+0xfb/0x140 drivers/base/core.c:4902
 __dev_printk+0xf5/0x270 drivers/base/core.c:4914
 _dev_err+0xe5/0x120 drivers/base/core.c:4957
 hub_port_init+0xd06/0x3a40 drivers/usb/core/hub.c:5082
 hub_port_connect drivers/usb/core/hub.c:5462 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5673 [inline]
 port_event drivers/usb/core/hub.c:5833 [inline]
 hub_event+0x2b4f/0x4e10 drivers/usb/core/hub.c:5915
 process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3238
 process_scheduled_works kernel/workqueue.c:3319 [inline]
 worker_thread+0x6c8/0xf00 kernel/workqueue.c:3400
 kthread+0x3af/0x750 kernel/kthread.c:464
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>