INFO: task syz.7.1968:14069 blocked for more than 144 seconds. Not tainted 6.12.0-rc5-syzkaller-00047-g4236f913808c #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.7.1968 state:D stack:27360 pid:14069 tgid:14068 ppid:13571 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5328 [inline] __schedule+0x185a/0x4b70 kernel/sched/core.c:6690 __schedule_loop kernel/sched/core.c:6767 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6782 super_lock+0x335/0x400 fs/super.c:114 user_get_super+0xd2/0x180 fs/super.c:1000 quotactl_block fs/quota/quota.c:890 [inline] __do_sys_quotactl fs/quota/quota.c:955 [inline] __se_sys_quotactl+0x527/0xa30 fs/quota/quota.c:917 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fd36e77e719 RSP: 002b:00007fd36f4c5038 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3 RAX: ffffffffffffffda RBX: 00007fd36e935f80 RCX: 00007fd36e77e719 RDX: 0000000000000000 RSI: 0000000020002740 RDI: 0000000000000001 RBP: 00007fd36e7f132e R08: 0000000000000000 R09: 0000000000000000 R10: 00000000200028c0 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fd36e935f80 R15: 00007ffc41ac2258 Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6720 2 locks held by getty/5584: #0: ffff8880317cd0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002f062f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211 2 locks held by kworker/u8:11/12742: 1 lock held by syz.6.1773/13297: 2 locks held by syz.6.1773/13299: 1 lock held by syz.6.1773/13306: 2 locks held by syz.6.1773/13307: 1 lock held by syz.6.1773/13308: 1 lock held by syz.9.1798/13389: #0: ffff88802aaca0e0 (&type->s_umount_key#57/1){+.+.}-{3:3}, at: alloc_super+0x221/0x9d0 fs/super.c:344 4 locks held by syz-executor/13509: 2 locks held by syz-executor/14388: 1 lock held by syz.4.2167/14992: 9 locks held by syz-executor/15118: 6 locks held by syz.6.2196/15127: 3 locks held by syz.8.2203/15160: #0: ffff888068a610a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref drivers/tty/tty_ldisc.c:263 [inline] #0: ffff888068a610a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_flush+0x1f/0xc0 drivers/tty/tty_ldisc.c:386 #1: ffff88801aca10b8 (&buf->lock){+.+.}-{3:3}, at: tty_buffer_flush+0x79/0x3f0 drivers/tty/tty_buffer.c:229 #2: ffff888068a612e8 (&tty->termios_rwsem){++++}-{3:3}, at: n_tty_flush_buffer+0x31/0x240 drivers/tty/n_tty.c:358 1 lock held by syz.5.2206/15174: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.12.0-rc5-syzkaller-00047-g4236f913808c #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline] watchdog+0xff4/0x1040 kernel/hung_task.c:379 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 15118 Comm: syz-executor Not tainted 6.12.0-rc5-syzkaller-00047-g4236f913808c #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:__bfs kernel/locking/lockdep.c:1811 [inline] RIP: 0010:__bfs_backwards kernel/locking/lockdep.c:1856 [inline] RIP: 0010:check_irq_usage kernel/locking/lockdep.c:2827 [inline] RIP: 0010:check_prev_add kernel/locking/lockdep.c:3165 [inline] RIP: 0010:check_prevs_add kernel/locking/lockdep.c:3280 [inline] RIP: 0010:validate_chain+0x1fc2/0x5920 kernel/locking/lockdep.c:3904 Code: 80 3c 20 00 74 08 4c 89 f7 e8 0a 56 8a 00 48 09 9c 24 98 00 00 00 4d 8b 3e 4d 39 f7 0f 84 6e fc ff ff 41 b4 01 eb 0c 4d 8b 3f <4d> 39 f7 0f 84 5d fc ff ff 49 8d 5f 30 48 89 d8 48 c1 e8 03 48 b9 RSP: 0018:ffffc900045ceb40 EFLAGS: 00000046 RAX: 1ffffffff2d88b69 RBX: ffffffff96c45b78 RCX: dffffc0000000000 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff93c14e40 RBP: ffffc900045cee40 R08: ffffffff94296807 R09: 1ffffffff2852d00 R10: dffffc0000000000 R11: fffffbfff2852d01 R12: 0000000000000000 R13: ffffffff96c72af8 R14: ffffffff93c14e10 R15: ffffffff96c469b8 FS: 000055557caf8500(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f1b4f6656c0 CR3: 0000000081bc4000 CR4: 00000000003526f0 Call Trace: __lock_acquire+0x1384/0x2050 kernel/locking/lockdep.c:5202 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 alloc_object+0x1ba/0x6d0 lib/debugobjects.c:233 lookup_object_or_alloc lib/debugobjects.c:587 [inline] debug_object_activate+0x249/0x510 lib/debugobjects.c:710 debug_rcu_head_queue kernel/rcu/rcu.h:224 [inline] kvfree_call_rcu+0x99/0x790 kernel/rcu/tree.c:3801 neigh_flush_dev+0x188/0xaf0 net/core/neighbour.c:429 __neigh_ifdown+0x45/0x400 net/core/neighbour.c:446 neigh_ifdown+0x1f/0x30 net/core/neighbour.c:464 ndisc_netdev_event+0xcc/0x4e0 net/ipv6/ndisc.c:1922 notifier_call_chain+0x19f/0x3e0 kernel/notifier.c:93 call_netdevice_notifiers_extack net/core/dev.c:2034 [inline] call_netdevice_notifiers net/core/dev.c:2048 [inline] dev_close_many+0x33c/0x4c0 net/core/dev.c:1589 unregister_netdevice_many_notify+0x530/0x1da0 net/core/dev.c:11377 unregister_netdevice_many net/core/dev.c:11465 [inline] unregister_netdevice_queue+0x303/0x370 net/core/dev.c:11339 unregister_netdevice include/linux/netdevice.h:3118 [inline] nsim_destroy+0x180/0x5c0 drivers/net/netdevsim/netdev.c:778 __nsim_dev_port_del+0x14b/0x1b0 drivers/net/netdevsim/dev.c:1428 nsim_dev_port_del_all drivers/net/netdevsim/dev.c:1440 [inline] nsim_dev_reload_destroy+0x28a/0x490 drivers/net/netdevsim/dev.c:1661 nsim_drv_remove+0x58/0x160 drivers/net/netdevsim/dev.c:1676 device_remove drivers/base/dd.c:567 [inline] __device_release_driver drivers/base/dd.c:1273 [inline] device_release_driver_internal+0x4a9/0x7c0 drivers/base/dd.c:1296 bus_remove_device+0x34f/0x420 drivers/base/bus.c:576 device_del+0x57a/0x9b0 drivers/base/core.c:3864 device_unregister+0x20/0xc0 drivers/base/core.c:3905 nsim_bus_dev_del drivers/net/netdevsim/bus.c:462 [inline] del_device_store+0x363/0x480 drivers/net/netdevsim/bus.c:226 kernfs_fop_write_iter+0x3a0/0x500 fs/kernfs/file.c:334 new_sync_write fs/read_write.c:590 [inline] vfs_write+0xaeb/0xd30 fs/read_write.c:683 ksys_write+0x183/0x2b0 fs/read_write.c:736 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fa15077d1ff Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 c9 8d 02 00 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 1c 8e 02 00 48 RSP: 002b:00007ffecdd04fa0 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00007fa15077d1ff RDX: 0000000000000001 RSI: 00007ffecdd04ff0 RDI: 0000000000000005 RBP: 00007fa1507f2446 R08: 0000000000000000 R09: 00007ffecdd04df7 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000001 R13: 00007ffecdd04ff0 R14: 00007fa151464620 R15: 0000000000000003