INFO: task syz-executor.2:10976 blocked for more than 143 seconds. Not tainted 6.9.0-rc5-syzkaller-00042-ge88c4cfcb7b8 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.2 state:D stack:25648 pid:10976 tgid:10974 ppid:10048 flags:0x00000006 Call Trace: context_switch kernel/sched/core.c:5409 [inline] __schedule+0x1796/0x4a00 kernel/sched/core.c:6746 __schedule_loop kernel/sched/core.c:6823 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6838 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6895 rwsem_down_write_slowpath+0xeeb/0x13b0 kernel/locking/rwsem.c:1178 __down_write_common+0x1af/0x200 kernel/locking/rwsem.c:1306 inode_lock include/linux/fs.h:795 [inline] chown_common+0x3e1/0x850 fs/open.c:780 do_fchownat+0x16d/0x250 fs/open.c:821 __do_sys_lchown fs/open.c:846 [inline] __se_sys_lchown fs/open.c:844 [inline] __x64_sys_lchown+0x85/0xa0 fs/open.c:844 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f22aae7dea9 RSP: 002b:00007f22abbe60c8 EFLAGS: 00000246 ORIG_RAX: 000000000000005e RAX: ffffffffffffffda RBX: 00007f22aafac050 RCX: 00007f22aae7dea9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000040 RBP: 00007f22aaeca4a4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000006e R14: 00007f22aafac050 R15: 00007ffd4a06ff68 Showing all locks held in the system: 1 lock held by pool_workqueue_/3: 1 lock held by khungtaskd/29: #0: ffffffff8e334d20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline] #0: ffffffff8e334d20 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline] #0: ffffffff8e334d20 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6614 3 locks held by kworker/0:2/783: #0: ffff888015080948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3229 [inline] #0: ffff888015080948 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x8e0/0x17c0 kernel/workqueue.c:3335 #1: ffffc900043dfd00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3230 [inline] #1: ffffc900043dfd00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x91b/0x17c0 kernel/workqueue.c:3335 #2: ffffffff8f594988 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:276 5 locks held by kworker/u8:5/1044: 3 locks held by kworker/u8:7/2768: #0: ffff88802ac19148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3229 [inline] #0: ffff88802ac19148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x8e0/0x17c0 kernel/workqueue.c:3335 #1: ffffc9000ac2fd00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3230 [inline] #1: ffffc9000ac2fd00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x91b/0x17c0 kernel/workqueue.c:3335 #2: ffffffff8f594988 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xd0/0x16f0 net/ipv6/addrconf.c:4192 1 lock held by dhcpcd/4738: #0: ffffffff8f594988 (rtnl_mutex){+.+.}-{3:3}, at: devinet_ioctl+0x2ce/0x1bc0 net/ipv4/devinet.c:1096 2 locks held by getty/4825: #0: ffff88802fe310a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002f162f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6b5/0x1e10 drivers/tty/n_tty.c:2201 3 locks held by syz-executor.2/10975: 2 locks held by syz-executor.2/10976: #0: ffff888054230420 (sb_writers#16){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:409 #1: ffff88805ebda9e8 (&sb->s_type->i_mutex_key#22){++++}-{3:3}, at: inode_lock include/linux/fs.h:795 [inline] #1: ffff88805ebda9e8 (&sb->s_type->i_mutex_key#22){++++}-{3:3}, at: chown_common+0x3e1/0x850 fs/open.c:780 2 locks held by syz-executor.4/12999: #0: ffff88806034a0e0 (&type->s_umount_key#69){++++}-{3:3}, at: __super_lock fs/super.c:56 [inline] #0: ffff88806034a0e0 (&type->s_umount_key#69){++++}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff88806034a0e0 (&type->s_umount_key#69){++++}-{3:3}, at: deactivate_super+0xb5/0xf0 fs/super.c:504 #1: ffffffff8e33a0b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:291 [inline] #1: ffffffff8e33a0b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x39a/0x820 kernel/rcu/tree_exp.h:939 7 locks held by syz-executor.2/13274: #0: ffff88801dc98420 (sb_writers#8){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2855 [inline] #0: ffff88801dc98420 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x233/0xcb0 fs/read_write.c:586 #1: ffff88807aed1c88 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1eb/0x500 fs/kernfs/file.c:325 #2: ffff888023471b48 (kn->active#50){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x20f/0x500 fs/kernfs/file.c:326 #3: ffffffff8eed24e8 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: del_device_store+0xfc/0x480 drivers/net/netdevsim/bus.c:216 #4: ffff88801ef4b0e8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:990 [inline] #4: ffff88801ef4b0e8 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1093 [inline] #4: ffff88801ef4b0e8 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0xce/0x7c0 drivers/base/dd.c:1290 #5: ffff88801ef4a250 (&devlink->lock_key#51){+.+.}-{3:3}, at: nsim_drv_remove+0x50/0x160 drivers/net/netdevsim/dev.c:1672 #6: ffffffff8f594988 (rtnl_mutex){+.+.}-{3:3}, at: unregister_nexthop_notifier+0x17/0x40 net/ipv4/nexthop.c:3899 4 locks held by syz-executor.3/13279: #0: ffff88801dc98420 (sb_writers#8){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2855 [inline] #0: ffff88801dc98420 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x233/0xcb0 fs/read_write.c:586 #1: ffff88807f56cc88 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1eb/0x500 fs/kernfs/file.c:325 #2: ffff888023471b48 (kn->active#50){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x20f/0x500 fs/kernfs/file.c:326 #3: ffffffff8eed24e8 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: del_device_store+0xfc/0x480 drivers/net/netdevsim/bus.c:216 1 lock held by syz-executor.0/13482: #0: ffff88806034a0e0 (&type->s_umount_key#69){++++}-{3:3}, at: __super_lock fs/super.c:58 [inline] #0: ffff88806034a0e0 (&type->s_umount_key#69){++++}-{3:3}, at: super_lock+0x27c/0x400 fs/super.c:120 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 29 Comm: khungtaskd Not tainted 6.9.0-rc5-syzkaller-00042-ge88c4cfcb7b8 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114 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:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline] watchdog+0xfde/0x1020 kernel/hung_task.c:380 kthread+0x2f0/0x390 kernel/kthread.c:388 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 1 to CPUs 0: NMI backtrace for cpu 0 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline] NMI backtrace for cpu 0 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:86 [inline] NMI backtrace for cpu 0 skipped: idling at acpi_safe_halt+0x21/0x30 drivers/acpi/processor_idle.c:112