INFO: task syz-executor:7571 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:21592 pid:7571 tgid:7571 ppid:1 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x145f/0x5070 kernel/sched/core.c:6863 __schedule_loop kernel/sched/core.c:6945 [inline] rt_mutex_schedule+0x77/0xf0 kernel/sched/core.c:7241 rt_mutex_slowlock_block+0x5ba/0x6d0 kernel/locking/rtmutex.c:1647 __rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline] __rt_mutex_slowlock_locked kernel/locking/rtmutex.c:1760 [inline] rt_mutex_slowlock+0x2a8/0x6b0 kernel/locking/rtmutex.c:1800 __rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline] __mutex_lock_common kernel/locking/rtmutex_api.c:534 [inline] mutex_lock_nested+0x16a/0x1d0 kernel/locking/rtmutex_api.c:552 lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443 jfs_umount+0x2ef/0x3c0 fs/jfs/jfs_umount.c:114 jfs_put_super+0x8c/0x190 fs/jfs/super.c:194 generic_shutdown_super+0x135/0x2c0 fs/super.c:643 kill_block_super+0x44/0x90 fs/super.c:1722 deactivate_locked_super+0xbc/0x130 fs/super.c:474 cleanup_mnt+0x425/0x4c0 fs/namespace.c:1318 task_work_run+0x1d4/0x260 kernel/task_work.c:233 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] __exit_to_user_mode_loop kernel/entry/common.c:44 [inline] exit_to_user_mode_loop+0xef/0x4e0 kernel/entry/common.c:75 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline] do_syscall_64+0x2b7/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fbd1c2a0a77 RSP: 002b:00007ffc1d6fe068 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007fbd1c323d7d RCX: 00007fbd1c2a0a77 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffc1d6fe120 RBP: 00007ffc1d6fe120 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffc1d6ff1b0 R13: 00007fbd1c323d7d R14: 000000000004370e R15: 00007ffc1d6ff1f0 Showing all locks held in the system: 4 locks held by rcuc/0/20: #0: ffff8880b883b6d8 (&rq->__lock){-...}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:639 #1: ffff8880b8824688 (psi_seq){-...}-{0:0}, at: psi_task_switch+0x53/0x880 kernel/sched/psi.c:933 #2: ffffffff98f2db20 (&obj_hash[i].lock){-...}-{2:2}, at: debug_object_activate+0x72/0x4e0 lib/debugobjects.c:818 #3: ffffffff8d5ae940 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #3: ffffffff8d5ae940 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #3: ffffffff8d5ae940 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1195 [inline] #3: ffffffff8d5ae940 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0xa5/0x23d0 arch/x86/kernel/unwind_orc.c:495 1 lock held by khungtaskd/38: #0: ffffffff8d5ae940 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8d5ae940 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8d5ae940 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 7 locks held by kworker/u8:15/3444: #0: ffff888019ad4938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline] #0: ffff888019ad4938 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1770 kernel/workqueue.c:3340 #1: ffffc9000d007bc0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline] #1: ffffc9000d007bc0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1770 kernel/workqueue.c:3340 #2: ffffffff8e898720 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x7b0 net/core/net_namespace.c:670 #3: ffff88803ae6d0d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline] #3: ffff88803ae6d0d8 (&dev->mutex){....}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:108 [inline] #3: ffff88803ae6d0d8 (&dev->mutex){....}-{4:4}, at: devlink_pernet_pre_exit+0x10a/0x3d0 net/devlink/core.c:506 #4: ffff88803ae6b300 (&devlink->lock_key#21){+.+.}-{4:4}, at: devl_lock net/devlink/core.c:276 [inline] #4: ffff88803ae6b300 (&devlink->lock_key#21){+.+.}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:109 [inline] #4: ffff88803ae6b300 (&devlink->lock_key#21){+.+.}-{4:4}, at: devlink_pernet_pre_exit+0x11c/0x3d0 net/devlink/core.c:506 #5: ffffffff8e8a5838 (rtnl_mutex){+.+.}-{4:4}, at: nsim_destroy+0xed/0x680 drivers/net/netdevsim/netdev.c:1175 #6: ffff8880275e8e98 (&dev_instance_lock_key#20){+.+.}-{4:4}, at: netdev_lock include/linux/netdevice.h:2781 [inline] #6: ffff8880275e8e98 (&dev_instance_lock_key#20){+.+.}-{4:4}, at: unregister_netdevice_many_notify+0x58b/0x2330 net/core/dev.c:12343 2 locks held by getty/5560: #0: ffff888143b0f0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90003e8b2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x44f/0x1460 drivers/tty/n_tty.c:2211 3 locks held by kworker/1:5/5886: #0: ffff88813ff55138 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline] #0: ffff88813ff55138 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1770 kernel/workqueue.c:3340 #1: ffffc900051dfbc0 (deferred_process_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline] #1: ffffc900051dfbc0 (deferred_process_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1770 kernel/workqueue.c:3340 #2: ffffffff8e8a5838 (rtnl_mutex){+.+.}-{4:4}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104 2 locks held by syz-executor/7144: #0: ffff88805379c0d0 (&type->s_umount_key#68){++++}-{4:4}, at: __super_lock fs/super.c:57 [inline] #0: ffff88805379c0d0 (&type->s_umount_key#68){++++}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline] #0: ffff88805379c0d0 (&type->s_umount_key#68){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506 #1: ffffffff8d9f9ad8 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443 2 locks held by syz-executor/7461: #0: ffff88805c4660d0 (&type->s_umount_key#68){++++}-{4:4}, at: __super_lock fs/super.c:57 [inline] #0: ffff88805c4660d0 (&type->s_umount_key#68){++++}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline] #0: ffff88805c4660d0 (&type->s_umount_key#68){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506 #1: ffffffff8d9f9ad8 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443 3 locks held by kworker/u8:23/7508: #0: ffff88813ff69938 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline] #0: ffff88813ff69938 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1770 kernel/workqueue.c:3340 #1: ffffc9000f91fbc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline] #1: ffffc9000f91fbc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1770 kernel/workqueue.c:3340 #2: ffffffff8e8a5838 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:303 2 locks held by syz-executor/7571: #0: ffff88805bf200d0 (&type->s_umount_key#68){++++}-{4:4}, at: __super_lock fs/super.c:57 [inline] #0: ffff88805bf200d0 (&type->s_umount_key#68){++++}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline] #0: ffff88805bf200d0 (&type->s_umount_key#68){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506 #1: ffffffff8d9f9ad8 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443 3 locks held by kworker/u8:31/8082: #0: ffff888030410138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline] #0: ffff888030410138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1770 kernel/workqueue.c:3340 #1: ffffc90003e97bc0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline] #1: ffffc90003e97bc0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1770 kernel/workqueue.c:3340 #2: ffffffff8e8a5838 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #2: ffffffff8e8a5838 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x119/0x15a0 net/ipv6/addrconf.c:4194 1 lock held by syz-executor/8516: #0: ffffffff8e8a5838 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #0: ffffffff8e8a5838 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #0: ffffffff8e8a5838 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8ec/0x1c90 net/core/rtnetlink.c:4071 1 lock held by syz-executor/8555: #0: ffffffff8e8a5838 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff8e8a5838 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x3b0/0x18b0 net/ipv4/devinet.c:978 1 lock held by syz-executor/8580: #0: ffffffff8e8a5838 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff8e8a5838 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x3b0/0x18b0 net/ipv4/devinet.c:978 7 locks held by syz-executor/8605: #0: ffff88803590a480 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2681 [inline] #0: ffff88803590a480 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x217/0xb40 fs/read_write.c:682 #1: ffff88805dbc4078 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1df/0x540 fs/kernfs/file.c:343 #2: ffff888142b541e8 (kn->active#52){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline] #2: ffff888142b541e8 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x232/0x540 fs/kernfs/file.c:344 #3: ffffffff8e12c6f8 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x360 drivers/net/netdevsim/bus.c:234 #4: ffff88802d8f10d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline] #4: ffff88802d8f10d8 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1104 [inline] #4: ffff88802d8f10d8 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xb6/0x800 drivers/base/dd.c:1302 #5: ffff88801f7ee300 (&devlink->lock_key#20){+.+.}-{4:4}, at: nsim_drv_remove+0x50/0x160 drivers/net/netdevsim/dev.c:1777 #6: ffffffff8e8a5838 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #6: ffffffff8e8a5838 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_dev_lock+0x257/0x2f0 net/core/dev.c:2143 2 locks held by syz-executor/8765: #0: ffffffff8e021d88 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e021d88 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8e021d88 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570 #1: ffffffff8e8a5838 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #1: ffffffff8e8a5838 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #1: ffffffff8e8a5838 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8ec/0x1c90 net/core/rtnetlink.c:4071 3 locks held by dhcpcd-run-hook/8868: 7 locks held by dhcpcd-run-hook/8874: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] __sys_info lib/sys_info.c:157 [inline] sys_info+0x135/0x170 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline] watchdog+0xf95/0xfe0 kernel/hung_task.c:515 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x510/0xa50 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 8874 Comm: dhcpcd-run-hook Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:flush_tlb_func+0x421/0x610 arch/x86/mm/tlb.c:1273 Code: b0 a9 41 8d e8 50 1d ac 00 48 83 3d 88 e3 cb 0b 00 0f 84 f5 01 00 00 4c 89 e7 e8 2a 1f 00 00 90 48 8b 44 24 40 42 0f b6 04 28 <84> c0 75 45 48 8b 04 24 44 0f b6 38 49 83 ff 40 73 4d 41 bd 01 00 RSP: 0000:ffffc900047379b0 EFLAGS: 00000046 RAX: 0000000000000000 RBX: ffff8880b883a2c0 RCX: 000000000000000c RDX: 0000000000000000 RSI: 0000000000000008 RDI: 000056150b36c000 RBP: 1ffff11017107458 R08: ffff88804dedd5df R09: 1ffff11009bdbabb R10: dffffc0000000000 R11: ffffed1009bdbabc R12: 000056150b36c000 R13: dffffc0000000000 R14: 1ffffffff1a83536 R15: 000000000000000c FS: 00007f2e8cc5fc80(0000) GS:ffff888126cef000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000056150b36c6c0 CR3: 00000000317aa000 CR4: 00000000003526f0 Call Trace: flush_tlb_mm_range+0xae5/0x1170 arch/x86/mm/tlb.c:1477 flush_tlb_page arch/x86/include/asm/tlbflush.h:324 [inline] ptep_clear_flush+0x120/0x170 mm/pgtable-generic.c:103 wp_page_copy mm/memory.c:3785 [inline] do_wp_page+0x1b94/0x4970 mm/memory.c:4180 handle_pte_fault mm/memory.c:6289 [inline] __handle_mm_fault mm/memory.c:6411 [inline] handle_mm_fault+0x9f6/0x1330 mm/memory.c:6580 do_user_addr_fault+0xa7c/0x1380 arch/x86/mm/fault.c:1336 handle_page_fault arch/x86/mm/fault.c:1476 [inline] exc_page_fault+0x71/0xd0 arch/x86/mm/fault.c:1532 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618 RIP: 0033:0x7f2e8cdc0b8e Code: 48 8d 05 55 8f 13 00 48 39 c5 0f 95 c0 0f b6 c0 48 c1 e0 02 48 09 d8 48 83 c8 01 49 89 45 08 48 89 c8 48 83 c8 01 48 89 42 08 <4b> 89 4c 35 00 8b 05 c3 f6 13 00 49 8d 4d 10 85 c0 0f 84 29 fa ff RSP: 002b:00007ffc20117190 EFLAGS: 00010206 RAX: 00000000000016b1 RBX: 0000000000000210 RCX: 00000000000016b0 RDX: 000056150b36b010 RSI: 00007f2e8cefa180 RDI: 000056150b36ae00 RBP: 00007f2e8cef9ac0 R08: 00007f2e8cef9ac0 R09: 0000000000000210 R10: 0000000000000003 R11: 0000000000000001 R12: 0000000000000200 R13: 000056150b36ae00 R14: 00000000000018c0 R15: 00007f2e8cef9b20