INFO: task kworker/u8:12:8751 blocked for more than 144 seconds. Not tainted 6.13.0-syzkaller-00164-g100ceb4817a2 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:12 state:D stack:20816 pid:8751 tgid:8751 ppid:2 flags:0x00004000 Workqueue: events_unbound netfs_write_collection_worker Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0x17fb/0x4be0 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6848 bit_wait+0x12/0xd0 kernel/sched/wait_bit.c:237 __wait_on_bit+0xb0/0x2f0 kernel/sched/wait_bit.c:49 out_of_line_wait_on_bit+0x1d5/0x260 kernel/sched/wait_bit.c:64 wait_on_bit include/linux/wait_bit.h:77 [inline] netfs_retry_writes+0x16e/0x19b0 fs/netfs/write_retry.c:215 netfs_collect_write_results fs/netfs/write_collect.c:352 [inline] netfs_write_collection_worker+0x2f90/0x3bb0 fs/netfs/write_collect.c:374 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3317 worker_thread+0x870/0xd30 kernel/workqueue.c:3398 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 INFO: task syz.6.2365:14685 blocked for more than 145 seconds. Not tainted 6.13.0-syzkaller-00164-g100ceb4817a2 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.6.2365 state:D stack:24128 pid:14685 tgid:14685 ppid:7585 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0x17fb/0x4be0 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6848 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6905 __mutex_lock_common kernel/locking/mutex.c:665 [inline] __mutex_lock+0x7e7/0xee0 kernel/locking/mutex.c:735 netfs_writepages+0x12b/0x9e0 fs/netfs/write_issue.c:564 do_writepages+0x35f/0x880 mm/page-writeback.c:2708 filemap_fdatawrite_wbc mm/filemap.c:388 [inline] __filemap_fdatawrite_range mm/filemap.c:421 [inline] __filemap_fdatawrite mm/filemap.c:427 [inline] filemap_fdatawrite+0x1f3/0x2a0 mm/filemap.c:432 v9fs_dir_release+0x151/0x560 fs/9p/vfs_dir.c:219 __fput+0x23c/0xa50 fs/file_table.c:450 task_work_run+0x24f/0x310 kernel/task_work.c:239 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop kernel/entry/common.c:114 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x13f/0x340 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f5ae9785d29 RSP: 002b:00007ffe08ef3228 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007f5ae9977ba0 RCX: 00007f5ae9785d29 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007f5ae9977ba0 R08: 000000000000012c R09: 00007ffe08ef351f R10: 00007f5ae9977ac0 R11: 0000000000000246 R12: 00000000000ec467 R13: 00007ffe08ef3330 R14: 0000000000000032 R15: ffffffffffffffff Showing all locks held in the system: 1 lock held by pool_workqueue_/3: 3 locks held by kworker/u8:1/12: 1 lock held by khungtaskd/30: #0: ffffffff8e937da0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e937da0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e937da0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6744 4 locks held by kworker/u8:6/2978: #0: ffff88801baeb148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff88801baeb148 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1840 kernel/workqueue.c:3317 #1: ffffc9000b667d00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc9000b667d00 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1840 kernel/workqueue.c:3317 #2: ffffffff8fc9ba10 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0x16a/0xd50 net/core/net_namespace.c:602 #3: ffffffff8fca7ec8 (rtnl_mutex){+.+.}-{4:4}, at: mpls_net_exit+0x7d/0x2a0 net/mpls/af_mpls.c:2706 3 locks held by kworker/u8:9/3427: #0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1840 kernel/workqueue.c:3317 #1: ffffc9000bdc7d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc9000bdc7d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1840 kernel/workqueue.c:3317 #2: ffffffff8fca7ec8 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:285 1 lock held by dhcpcd/5489: #0: ffffffff8fca7ec8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fca7ec8 (rtnl_mutex){+.+.}-{4:4}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6928 2 locks held by getty/5579: #0: ffff8880314970a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002fde2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211 2 locks held by kworker/u8:12/8751: #0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1840 kernel/workqueue.c:3317 #1: ffffc90003347d00 ((work_completion)(&rreq->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc90003347d00 ((work_completion)(&rreq->work)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1840 kernel/workqueue.c:3317 2 locks held by kworker/u8:22/13113: 1 lock held by syz-executor/14302: #0: ffffffff8fca7ec8 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:698 [inline] #0: ffffffff8fca7ec8 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3b/0x1b0 drivers/net/tun.c:3517 1 lock held by syz.6.2365/14685: #0: ffff888023750b70 (&ctx->wb_lock){+.+.}-{4:4}, at: netfs_writepages+0x12b/0x9e0 fs/netfs/write_issue.c:564 1 lock held by syz.6.2365/14688: #0: ffff888023750b70 (&ctx->wb_lock){+.+.}-{4:4}, at: netfs_writepages+0xcf/0x9e0 fs/netfs/write_issue.c:558 1 lock held by syz.8.2475/15400: #0: ffffffff8fca7ec8 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:698 [inline] #0: ffffffff8fca7ec8 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3b/0x1b0 drivers/net/tun.c:3517 7 locks held by syz-executor/15714: #0: ffff888035bda420 (sb_writers#8){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2979 [inline] #0: ffff888035bda420 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x225/0xd30 fs/read_write.c:675 #1: ffff888033ee9c88 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1ea/0x500 fs/kernfs/file.c:325 #2: ffff8880278ef1e8 (kn->active#49){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x20e/0x500 fs/kernfs/file.c:326 #3: ffffffff8f553908 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xfc/0x480 drivers/net/netdevsim/bus.c:216 #4: ffff88806170c0e8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1014 [inline] #4: ffff88806170c0e8 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1095 [inline] #4: ffff88806170c0e8 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xce/0x7c0 drivers/base/dd.c:1293 #5: ffff88806170a250 (&devlink->lock_key#12){+.+.}-{4:4}, at: nsim_drv_remove+0x50/0x160 drivers/net/netdevsim/dev.c:1675 #6: ffffffff8fca7ec8 (rtnl_mutex){+.+.}-{4:4}, at: nsim_destroy+0x71/0x5c0 drivers/net/netdevsim/netdev.c:816 1 lock held by syz.5.2604/15975: #0: ffffffff8e93d2b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:329 [inline] #0: ffffffff8e93d2b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:976 2 locks held by syz.0.2606/15988: #0: ffff888048650d80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:480 [inline] #0: ffff888048650d80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x203/0x510 net/bluetooth/hci_core.c:2697 #1: ffff888048650078 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x5c8/0x11c0 net/bluetooth/hci_sync.c:5201 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.13.0-syzkaller-00164-g100ceb4817a2 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 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:234 [inline] watchdog+0xff6/0x1040 kernel/hung_task.c:397 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 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:106 [inline] NMI backtrace for cpu 0 skipped: idling at acpi_safe_halt+0x21/0x30 drivers/acpi/processor_idle.c:111