syzbot

INFO: task init:1695 blocked for more than 143 seconds.
      Not tainted 6.15.0-rc6-syzkaller-00188-gfee3e843b309 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:init            state:D stack:28808 pid:1695  tgid:1695  ppid:1      task_flags:0x400140 flags:0x00004000
Call Trace:
 <TASK>
 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
 wait_for_device_probe+0x11d/0x1c0 drivers/base/dd.c:773
 device_shutdown+0x26/0x5c0 drivers/base/core.c:4796
 kernel_shutdown_prepare kernel/reboot.c:308 [inline]
 kernel_power_off+0x52/0xc0 kernel/reboot.c:707
 __do_sys_reboot kernel/reboot.c:783 [inline]
 __se_sys_reboot+0x3c3/0x3e0 kernel/reboot.c:728
 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: 0033:0x7f6e50a038d3
RSP: 002b:00007ffc9551ec48 EFLAGS: 00000246
 ORIG_RAX: 00000000000000a9
RAX: ffffffffffffffda RBX: 000000000000000c RCX: 00007f6e50a038d3
RDX: 000000004321fedc RSI: 0000000028121969 RDI: 00000000fee1dead
RBP: 000000004321fedc R08: 0000000000000000 R09: 0000000000000000
R10: 00007ffc9551ec20 R11: 0000000000000246 R12: 00007f6e50ba6490
R13: 00007ffc9551ec9c R14: 00007f6e50be6000 R15: 00005564b283fd98
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/31:
 #0: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 #0: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
 #0: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6764
10 locks held by kworker/1:2/1166:
1 lock held by init/1695:
 #0: ffffffff8ddedc68 (system_transition_mutex){+.+.}-{4:4}, at: __do_sys_reboot kernel/reboot.c:764 [inline]
 #0: ffffffff8ddedc68 (system_transition_mutex){+.+.}-{4:4}, at: __se_sys_reboot+0x3be/0x3e0 kernel/reboot.c:728

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

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc6-syzkaller-00188-gfee3e843b309 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
 <TASK>
 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+0x4b/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 1166 Comm: kworker/1:2 Not tainted 6.15.0-rc6-syzkaller-00188-gfee3e843b309 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: usb_hub_wq hub_event
RIP: 0010:printk_get_console_flush_type+0x1/0x460 kernel/printk/internal.h:237
Code: 8d e8 e3 f9 80 00 e9 10 ff ff ff 66 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 55 <41> 57 41 56 53 48 89 fb e8 92 00 1f 00 ba 04 00 00 00 48 89 df 31
RSP: 0018:ffffc90003aee430 EFLAGS: 00000202
RAX: 0000000000000001 RBX: ffffc90003aee5e0 RCX: 0000000003aee500
RDX: ffffc9001a44b000 RSI: 00000000000fffff RDI: ffffc90003aee520
RBP: ffffc90003aee590 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffffbfff1bc32c8 R12: dffffc0000000000
R13: dffffc0000000000 R14: ffffc90003aee5b8 R15: 0000000000000058
FS:  0000000000000000(0000) GS:ffff8881261c7000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa0b4bf84c0 CR3: 000000000dd38000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 console_flush_all+0x112/0xc40 kernel/printk/printk.c:3201
 __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
 dev_vprintk_emit+0x337/0x3f0 drivers/base/core.c:4917
 dev_printk_emit+0xe0/0x130 drivers/base/core.c:4928
 __netdev_printk+0x3d7/0x4d0 net/core/dev.c:12395
 netdev_warn+0x10a/0x160 net/core/dev.c:12448
 asix_write_cmd drivers/net/usb/asix_common.c:57 [inline]
 asix_set_sw_mii drivers/net/usb/asix_common.c:75 [inline]
 asix_check_host_enable drivers/net/usb/asix_common.c:98 [inline]
 __asix_mdio_read drivers/net/usb/asix_common.c:506 [inline]
 asix_mdio_read+0x1d8/0x530 drivers/net/usb/asix_common.c:529
 asix_phy_reset+0xbc/0x1b0 drivers/net/usb/asix_devices.c:215
 ax88172_bind+0x3f0/0x5e0 drivers/net/usb/asix_devices.c:275
 usbnet_probe+0x9e1/0x27b0 drivers/net/usb/usbnet.c:1772
 usb_probe_interface+0x641/0xbc0 drivers/usb/core/driver.c:396
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x26a/0x9a0 drivers/base/dd.c:657
 __driver_probe_device+0x18c/0x2f0 drivers/base/dd.c:799
 driver_probe_device+0x4f/0x430 drivers/base/dd.c:829
 __device_attach_driver+0x2ce/0x530 drivers/base/dd.c:957
 bus_for_each_drv+0x251/0x2e0 drivers/base/bus.c:462
 __device_attach+0x2b8/0x400 drivers/base/dd.c:1029
 bus_probe_device+0x185/0x260 drivers/base/bus.c:537
 device_add+0x7b6/0xb50 drivers/base/core.c:3692
 usb_set_configuration+0x1a87/0x20e0 drivers/usb/core/message.c:2210
 usb_generic_driver_probe+0x8d/0x150 drivers/usb/core/generic.c:250
 usb_probe_device+0x1c4/0x390 drivers/usb/core/driver.c:291
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x26a/0x9a0 drivers/base/dd.c:657
 __driver_probe_device+0x18c/0x2f0 drivers/base/dd.c:799
 driver_probe_device+0x4f/0x430 drivers/base/dd.c:829
 __device_attach_driver+0x2ce/0x530 drivers/base/dd.c:957
 bus_for_each_drv+0x251/0x2e0 drivers/base/bus.c:462
 __device_attach+0x2b8/0x400 drivers/base/dd.c:1029
 bus_probe_device+0x185/0x260 drivers/base/bus.c:537
 device_add+0x7b6/0xb50 drivers/base/core.c:3692
 usb_new_device+0xa39/0x16c0 drivers/usb/core/hub.c:2663
 hub_port_connect drivers/usb/core/hub.c:5531 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5671 [inline]
 port_event drivers/usb/core/hub.c:5831 [inline]
 hub_event+0x2941/0x4a00 drivers/usb/core/hub.c:5913
 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+0x4b/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>