INFO: task syz.5.1857:17370 blocked for more than 143 seconds. Not tainted 6.17.0-rc1-syzkaller-00004-g53e760d89498 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.5.1857 state:D stack:28088 pid:17370 tgid:17364 ppid:6684 task_flags:0x400140 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1190/0x5de0 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:7058 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7115 __mutex_lock_common kernel/locking/mutex.c:676 [inline] __mutex_lock+0x82a/0x10b0 kernel/locking/mutex.c:760 device_lock include/linux/device.h:911 [inline] usbdev_open+0x1b6/0x8b0 drivers/usb/core/devio.c:1054 chrdev_open+0x231/0x6a0 fs/char_dev.c:414 do_dentry_open+0x982/0x1530 fs/open.c:965 vfs_open+0x82/0x3f0 fs/open.c:1095 do_open fs/namei.c:3887 [inline] path_openat+0x1de4/0x2cb0 fs/namei.c:4046 do_filp_open+0x20b/0x470 fs/namei.c:4073 do_sys_openat2+0x11b/0x1d0 fs/open.c:1435 do_sys_open fs/open.c:1450 [inline] __do_sys_openat fs/open.c:1466 [inline] __se_sys_openat fs/open.c:1461 [inline] __x64_sys_openat+0x174/0x210 fs/open.c:1461 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7ff8ab18d550 RSP: 002b:00007ff8abfe7b70 EFLAGS: 00000293 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 000000000000a401 RCX: 00007ff8ab18d550 RDX: 000000000000a401 RSI: 00007ff8abfe7c10 RDI: 00000000ffffff9c RBP: 00007ff8abfe7c10 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: cccccccccccccccd R13: 00007ff8ab3b6128 R14: 00007ff8ab3b6090 R15: 00007fff6981df38 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e5c11e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e5c11e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e5c11e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6775 6 locks held by kworker/1:1/54: 4 locks held by kworker/u8:7/4480: 2 locks held by getty/5605: #0: ffff8880362520a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222 1 lock held by syz.5.1857/17370: #0: ffff888029966198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:911 [inline] #0: ffff888029966198 (&dev->mutex){....}-{4:4}, at: usbdev_open+0x1b6/0x8b0 drivers/usb/core/devio.c:1054 1 lock held by syz.6.2259/20466: 3 locks held by vhost-20470/20471: 1 lock held by syz.8.2260/20481: 2 locks held by syz.3.2262/20488: #0: ffff88802a07c250 (&devlink->lock_key#5){+.+.}-{4:4}, at: devlink_compat_flash_update+0xaf/0x360 net/devlink/dev.c:1235 #1: ffffffff8e475330 (umhelper_sem){++++}-{4:4}, at: usermodehelper_read_trylock+0xa9/0x250 kernel/umh.c:214 4 locks held by syz.3.2262/20491: #0: ffffffff8f302ec8 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x63/0x420 drivers/char/misc.c:125 #1: ffffffff8e484968 (system_transition_mutex){+.+.}-{4:4}, at: lock_system_sleep+0x87/0xa0 kernel/power/main.c:57 #2: ffffffff8e4c4dd0 ((pm_chain_head).rwsem){++++}-{4:4}, at: blocking_notifier_call_chain_robust kernel/notifier.c:344 [inline] #2: ffffffff8e4c4dd0 ((pm_chain_head).rwsem){++++}-{4:4}, at: blocking_notifier_call_chain_robust+0xa8/0x160 kernel/notifier.c:333 #3: ffffffff8e5cc640 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x48/0x6e0 kernel/rcu/tree.c:3815 6 locks held by syz.3.2262/20496: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.17.0-rc1-syzkaller-00004-g53e760d89498 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 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:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:328 [inline] watchdog+0xf0e/0x1260 kernel/hung_task.c:491 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148 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: 0 Comm: swapper/1 Not tainted 6.17.0-rc1-syzkaller-00004-g53e760d89498 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:82 Code: ac 62 02 c3 cc cc cc cc 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d b3 c2 16 00 fb f4 4c 0d 03 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90 RSP: 0018:ffffc90000197df8 EFLAGS: 000002c2 RAX: 0000000003b829ff RBX: 0000000000000001 RCX: ffffffff8b934c29 RDX: 0000000000000000 RSI: ffffffff8de4f175 RDI: ffffffff8c162480 RBP: ffffed1003c5d488 R08: 0000000000000001 R09: ffffed10170a6655 R10: ffff8880b85332ab R11: 0000000000000000 R12: 0000000000000001 R13: ffff88801e2ea440 R14: ffffffff90ab3590 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8881247bc000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000285030 CR3: 000000005a90d000 CR4: 00000000003526f0 Call Trace: arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline] default_idle+0x13/0x20 arch/x86/kernel/process.c:757 default_idle_call+0x6d/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:190 [inline] do_idle+0x391/0x510 kernel/sched/idle.c:330 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:428 start_secondary+0x21d/0x2b0 arch/x86/kernel/smpboot.c:315 common_startup_64+0x13e/0x148