INFO: task syz-executor:4259 blocked for more than 143 seconds. Not tainted 6.1.114-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:20112 pid:4259 ppid:1 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5241 [inline] __schedule+0x143f/0x4570 kernel/sched/core.c:6558 schedule+0xbf/0x180 kernel/sched/core.c:6634 wb_wait_for_completion+0x162/0x290 fs/fs-writeback.c:191 sync_inodes_sb+0x28f/0xb10 fs/fs-writeback.c:2739 sync_filesystem+0x16b/0x220 fs/sync.c:64 generic_shutdown_super+0x6b/0x340 fs/super.c:474 kill_block_super+0x7a/0xe0 fs/super.c:1470 deactivate_locked_super+0xa0/0x110 fs/super.c:332 cleanup_mnt+0x490/0x520 fs/namespace.c:1186 task_work_run+0x246/0x300 kernel/task_work.c:203 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0xde/0x100 kernel/entry/common.c:177 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:303 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f47d257fa47 RSP: 002b:00007ffd55276338 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007f47d25f11cc RCX: 00007f47d257fa47 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffd552763f0 RBP: 00007ffd552763f0 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffd55277470 R13: 00007f47d25f11cc R14: 000000000002a79f R15: 00007ffd552774b0 Showing all locks held in the system: 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8d32b1d0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:517 1 lock held by rcu_tasks_trace/13: #0: ffffffff8d32b9d0 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:517 3 locks held by kworker/1:0/22: #0: ffff888030cf9938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc900001c7d20 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #2: ffffffff8e4fafa8 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xcc/0x16b0 net/ipv6/addrconf.c:4115 1 lock held by khungtaskd/27: #0: ffffffff8d32b000 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #0: ffffffff8d32b000 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #0: ffffffff8d32b000 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6510 1 lock held by dhcpcd/3914: #0: ffffffff8e4fafa8 (rtnl_mutex){+.+.}-{3:3}, at: __netlink_dump_start+0x12e/0x6c0 net/netlink/af_netlink.c:2302 2 locks held by getty/4001: #0: ffff88803100e098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244 #1: ffffc900032462f0 (&ldata->atomic_read_lock){+.+.}-{3:3} , at: n_tty_read+0x6a7/0x1db0 drivers/tty/n_tty.c:2198 2 locks held by syz-executor/4259: #0: ffff8880784920e0 (&type->s_umount_key#82){+.+.}-{3:3}, at: deactivate_super+0xa9/0xe0 fs/super.c:362 #1: ffff8881433187d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:362 [inline] #1: ffff8881433187d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x270/0xb10 fs/fs-writeback.c:2737 2 locks held by kworker/1:7/4326: 6 locks held by kworker/u4:6/4365: #0: ffff888017e16938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc90004bf7d20 ( net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #2: ffffffff8e4eec50 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0xf1/0xb60 net/core/net_namespace.c:566 #3: ffff88805bb792f8 (&devlink->lock_key#2){+.+.}-{3:3}, at: devlink_pernet_pre_exit+0x132/0x2f0 net/devlink/leftover.c:12500 #4: ffffffff8e4fafa8 (rtnl_mutex){+.+.}-{3:3}, at: nsim_destroy+0x3a/0x140 drivers/net/netdevsim/netdev.c:381 #5: ffffffff8d3305f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline] #5: ffffffff8d3305f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x360/0x930 kernel/rcu/tree_exp.h:962 5 locks held by kworker/0:14/4436: #0: ffff88801e28c138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc90005547d20 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #2: ffff888144f0a190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:837 [inline] #2: ffff888144f0a190 (&dev->mutex){....}-{3:3}, at: hub_event+0x1fe/0x5730 drivers/usb/core/hub.c:5801 #3: ffff888077537190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:837 [inline] #3: ffff888077537190 (&dev->mutex){....}-{3:3}, at: usb_disconnect+0xfa/0x8c0 drivers/usb/core/hub.c:2266 #4: ffff888076c3a118 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:837 [inline] #4: ffff888076c3a118 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1080 [inline] #4: ffff888076c3a118 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0xb6/0x880 drivers/base/dd.c:1283 5 locks held by kworker/0:18/4561: #0: ffff88801e28c138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc90005b0fd20 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #2: ffff888144f72190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:837 [inline] #2: ffff888144f72190 (&dev->mutex){....}-{3:3}, at: hub_event+0x1fe/0x5730 drivers/usb/core/hub.c:5801 #3: ffff888075d25190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:837 [inline] #3: ffff888075d25190 (&dev->mutex){....}-{3:3}, at: __device_attach+0x8a/0x570 drivers/base/dd.c:990 #4: ffff88801d706118 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:837 [inline] #4: ffff88801d706118 (&dev->mutex){....}-{3:3}, at: __device_attach+0x8a/0x570 drivers/base/dd.c:990 2 locks held by kworker/1:16/5133: #0: ffff888017c72138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc900196a7d20 ((work_completion)(&rew->rew_work) ){+.+.}-{0:0} , at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 4 locks held by kworker/u4:15/5171: #0: ffff8881426fb138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc90018d7fd20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #2: ffff888078492650 (sb_internal#5){.+.+}-{0:0}, at: xfs_bmapi_convert_delalloc+0x263/0x12f0 fs/xfs/libxfs/xfs_bmap.c:4507 #3: ffff88805c801858 (&xfs_nondir_ilock_class){++++}-{3:3}, at: xfs_bmapi_convert_delalloc+0x291/0x12f0 fs/xfs/libxfs/xfs_bmap.c:4512 1 lock held by syz.1.775/7302: #0: ffffffff8d3305f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline] #0: ffffffff8d3305f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x360/0x930 kernel/rcu/tree_exp.h:962 1 lock held by syz-executor/7304: #0: ffffffff8e4fafa8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline] #0: ffffffff8e4fafa8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x7c1/0xff0 net/core/rtnetlink.c:6147 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 27 Comm: khungtaskd Not tainted 6.1.114-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106 nmi_cpu_backtrace+0x4e1/0x560 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x1ae/0x3f0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline] watchdog+0xf88/0xfd0 kernel/hung_task.c:377 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline] NMI backtrace for cpu 1 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline] NMI backtrace for cpu 1 skipped: idling at acpi_safe_halt drivers/acpi/processor_idle.c:111 [inline] NMI backtrace for cpu 1 skipped: idling at acpi_idle_do_entry+0x10f/0x340 drivers/acpi/processor_idle.c:567