INFO: task syz.8.408:8898 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.8.408 state:D stack:23896 pid:8898 tgid:8897 ppid:8520 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5260 [inline] __schedule+0x147b/0x4f50 kernel/sched/core.c:6867 __schedule_loop kernel/sched/core.c:6949 [inline] schedule+0x164/0x360 kernel/sched/core.c:6964 io_schedule+0x80/0xe0 kernel/sched/core.c:7791 folio_wait_bit_common+0x6dd/0xbc0 mm/filemap.c:1323 folio_lock include/linux/pagemap.h:1170 [inline] release_metapage+0x103/0xab0 fs/jfs/jfs_metapage.c:870 discard_metapage fs/jfs/jfs_metapage.h:88 [inline] __get_metapage+0x9a3/0xde0 fs/jfs/jfs_metapage.c:753 dtSplitPage+0x791/0x37c0 fs/jfs/jfs_dtree.c:1471 dtSplitUp fs/jfs/jfs_dtree.c:1092 [inline] dtInsert+0x107a/0x5de0 fs/jfs/jfs_dtree.c:871 jfs_mkdir+0x783/0xb00 fs/jfs/namei.c:270 vfs_mkdir+0x52c/0x5d0 fs/namei.c:5139 do_mkdirat+0x281/0x4c0 fs/namei.c:5173 __do_sys_mkdir fs/namei.c:5200 [inline] __se_sys_mkdir fs/namei.c:5198 [inline] __x64_sys_mkdir+0x6c/0x80 fs/namei.c:5198 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f84fb68acb9 RSP: 002b:00007f84f98e6028 EFLAGS: 00000246 ORIG_RAX: 0000000000000053 RAX: ffffffffffffffda RBX: 00007f84fb905fa0 RCX: 00007f84fb68acb9 RDX: 0000000000000000 RSI: 00000000000000a5 RDI: 00002000000000c0 RBP: 00007f84fb6f8bf7 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f84fb906038 R14: 00007f84fb905fa0 R15: 00007ffc15c2a978 Showing all locks held in the system: 1 lock held by khungtaskd/38: #0: ffffffff8d9c7780 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8d9c7780 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8d9c7780 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 4 locks held by kworker/u8:3/57: #0: ffff88801aa94938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline] #0: ffff88801aa94938 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0 kernel/workqueue.c:3340 #1: ffffc9000123fbc0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline] #1: ffffc9000123fbc0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0 kernel/workqueue.c:3340 #2: ffffffff8ed294e0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xfe/0x7b0 net/core/net_namespace.c:670 #3: ffffffff8ed37e78 (rtnl_mutex){+.+.}-{4:4}, at: wiphy_unregister+0x26a/0xad0 net/wireless/core.c:1180 1 lock held by udevd/5170: 1 lock held by dhcpcd/5465: #0: ffffffff8ed37e78 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff8ed37e78 (rtnl_mutex){+.+.}-{4:4}, at: inet6_rtm_newaddr+0x65f/0xe30 net/ipv6/addrconf.c:5027 2 locks held by getty/5560: #0: ffff88814eaa00a0 (&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+0x462/0x13c0 drivers/tty/n_tty.c:2211 3 locks held by kworker/u8:17/6152: #0: ffff888144682138 ((wq_completion)cfg80211){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline] #0: ffff888144682138 ((wq_completion)cfg80211){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0 kernel/workqueue.c:3340 #1: ffffc9000c3afbc0 ((work_completion)(&(&rdev->dfs_update_channels_wk)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline] #1: ffffc9000c3afbc0 ((work_completion)(&(&rdev->dfs_update_channels_wk)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0 kernel/workqueue.c:3340 #2: ffffffff8ed37e78 (rtnl_mutex){+.+.}-{4:4}, at: cfg80211_dfs_channels_update_work+0xd6/0x660 net/wireless/mlme.c:1040 4 locks held by kworker/u8:18/6158: #0: ffff888141aca938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline] #0: ffff888141aca938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0 kernel/workqueue.c:3340 #1: ffffc9000c4ffbc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline] #1: ffffc9000c4ffbc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0 kernel/workqueue.c:3340 #2: ffff88803c0020d0 (&type->s_umount_key#89){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:563 #3: ffff88805d211568 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x1ca/0x530 fs/jfs/inode.c:108 4 locks held by syz.8.408/8898: #0: ffff88803c002480 (sb_writers#17){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:499 #1: ffff88805d211938 (&type->i_mutex_dir_key#13/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1072 [inline] #1: ffff88805d211938 (&type->i_mutex_dir_key#13/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2873 [inline] #1: ffff88805d211938 (&type->i_mutex_dir_key#13/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2884 [inline] #1: ffff88805d211938 (&type->i_mutex_dir_key#13/1){+.+.}-{4:4}, at: filename_create+0x200/0x370 fs/namei.c:4888 #2: ffff88805d211568 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_mkdir+0x235/0xb00 fs/jfs/namei.c:233 #3: ffff88805d323c68 (&jfs_ip->commit_mutex/1){+.+.}-{4:4}, at: jfs_mkdir+0x250/0xb00 fs/jfs/namei.c:234 9 locks held by syz-executor/10488: 4 locks held by syz-executor/10510: #0: ffff8880353a6480 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2681 [inline] #0: ffff8880353a6480 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x22d/0xba0 fs/read_write.c:682 #1: ffff88805caad478 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1df/0x540 fs/kernfs/file.c:343 #2: ffff8880269a7b48 (kn->active#52){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline] #2: ffff8880269a7b48 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x232/0x540 fs/kernfs/file.c:344 #3: ffffffff8e5a8df8 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd7/0x370 drivers/net/netdevsim/bus.c:234 2 locks held by syz.9.685/10554: #0: ffff88803c0020d0 (&type->s_umount_key#89){++++}-{4:4}, at: __super_lock fs/super.c:59 [inline] #0: ffff88803c0020d0 (&type->s_umount_key#89){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:121 #1: ffff8880248fa8c0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:397 [inline] #1: ffff8880248fa8c0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1c5/0xc10 fs/fs-writeback.c:2897 2 locks held by syz.9.685/10581: #0: ffff88803c0020d0 (&type->s_umount_key#89){++++}-{4:4}, at: __super_lock fs/super.c:59 [inline] #0: ffff88803c0020d0 (&type->s_umount_key#89){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:121 #1: ffff8880248fa8c0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:397 [inline] #1: ffff8880248fa8c0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1c5/0xc10 fs/fs-writeback.c:2897 2 locks held by syz-executor/10652: #0: ffffffff8e497488 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e497488 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8e497488 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570 #1: ffffffff8ed37e78 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #1: ffffffff8ed37e78 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #1: ffffffff8ed37e78 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8a1/0x1be0 net/core/rtnetlink.c:4071 2 locks held by syz-executor/10702: #0: ffffffff8f27b360 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8f27b360 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8f27b360 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570 #1: ffffffff8ed37e78 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #1: ffffffff8ed37e78 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #1: ffffffff8ed37e78 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8a1/0x1be0 net/core/rtnetlink.c:4071 1 lock held by syz-executor/10730: #0: ffffffff8ed37e78 (rtnl_mutex){+.+.}-{4:4}, at: __tun_chr_ioctl+0x3bf/0x1e10 drivers/net/tun.c:3078 1 lock held by udevd/10773: #0: ffff8880493fba08 (&ep->lock){+.+.}-{3:3}, at: spin_lock_irq include/linux/spinlock_rt.h:93 [inline] #0: ffff8880493fba08 (&ep->lock){+.+.}-{3:3}, at: ep_poll fs/eventpoll.c:2040 [inline] #0: ffff8880493fba08 (&ep->lock){+.+.}-{3:3}, at: do_epoll_wait+0x851/0xbd0 fs/eventpoll.c:2461 ============================================= NMI backtrace for cpu 0 CPU: 0 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:161 [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+0xf90/0xfe0 kernel/hung_task.c:515 kthread+0x726/0x8b0 kernel/kthread.c:463 ret_from_fork+0x51b/0xa40 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 10488 Comm: syz-executor Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:trace_lock_acquire include/trace/events/lock.h:24 [inline] RIP: 0010:lock_acquire+0x58/0x330 kernel/locking/lockdep.c:5831 Code: 8b 05 6c 6d 64 10 48 89 44 24 58 0f 1f 44 00 00 65 8b 05 6f 6d 64 10 83 f8 08 0f 83 83 01 00 00 89 c0 48 0f a3 05 98 cb 89 0d <73> 0d e8 81 39 09 00 84 c0 0f 84 ca 01 00 00 83 3d 82 db 89 0d 00 RSP: 0018:ffffc9000d23edf8 EFLAGS: 00000297 RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0000000000000002 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8d9c7780 RBP: ffffffff8174b0b5 R08: 0000000000000000 R09: 0000000000000000 R10: ffffc9000d23efb8 R11: ffffffff81ad1390 R12: 0000000000000002 R13: ffffffff8d9c7780 R14: 0000000000000000 R15: 0000000000000000 FS: 000055556ee2d500(0000) GS:ffff8881268fc000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055b791443c18 CR3: 0000000027252000 CR4: 00000000003526f0 Call Trace: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:867 [inline] class_rcu_constructor include/linux/rcupdate.h:1195 [inline] unwind_next_frame+0xc2/0x23c0 arch/x86/kernel/unwind_orc.c:495 arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122 kasan_save_stack+0x3e/0x60 mm/kasan/common.c:57 kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:556 __call_rcu_common kernel/rcu/tree.c:3119 [inline] call_rcu+0xee/0x890 kernel/rcu/tree.c:3239 kernfs_put+0x191/0x470 fs/kernfs/dir.c:591 kernfs_remove_by_name_ns+0xb7/0x130 fs/kernfs/dir.c:1723 kernfs_remove_by_name include/linux/kernfs.h:633 [inline] remove_files fs/sysfs/group.c:28 [inline] sysfs_remove_group+0xfc/0x2e0 fs/sysfs/group.c:328 sysfs_remove_groups+0x54/0xb0 fs/sysfs/group.c:352 device_remove_groups drivers/base/core.c:2843 [inline] device_remove_attrs+0x1cb/0x280 drivers/base/core.c:2973 device_del+0x523/0x900 drivers/base/core.c:3877 unregister_netdevice_many_notify+0x1dfa/0x2360 net/core/dev.c:12431 unregister_netdevice_many net/core/dev.c:12459 [inline] unregister_netdevice_queue+0x31f/0x360 net/core/dev.c:12273 unregister_netdevice include/linux/netdevice.h:3405 [inline] nsim_destroy+0x1e5/0x680 drivers/net/netdevsim/netdev.c:1180 __nsim_dev_port_del+0x14d/0x1b0 drivers/net/netdevsim/dev.c:1528 nsim_dev_port_del_all drivers/net/netdevsim/dev.c:1540 [inline] nsim_dev_reload_destroy+0x288/0x490 drivers/net/netdevsim/dev.c:1763 nsim_drv_remove+0x58/0x160 drivers/net/netdevsim/dev.c:1778 device_remove drivers/base/dd.c:569 [inline] __device_release_driver drivers/base/dd.c:1282 [inline] device_release_driver_internal+0x46f/0x800 drivers/base/dd.c:1305 bus_remove_device+0x352/0x440 drivers/base/bus.c:616 device_del+0x52b/0x900 drivers/base/core.c:3878 device_unregister+0x21/0xf0 drivers/base/core.c:3919 nsim_bus_dev_del drivers/net/netdevsim/bus.c:491 [inline] del_device_store+0x2b0/0x370 drivers/net/netdevsim/bus.c:244 kernfs_fop_write_iter+0x3b0/0x540 fs/kernfs/file.c:352 new_sync_write fs/read_write.c:593 [inline] vfs_write+0x629/0xba0 fs/read_write.c:686 ksys_write+0x156/0x270 fs/read_write.c:738 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f54dd16b58e Code: 08 0f 85 a5 a8 ff ff 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 80 00 00 00 00 48 83 ec 08 RSP: 002b:00007ffe824ce588 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 000055556ee2d500 RCX: 00007f54dd16b58e RDX: 0000000000000001 RSI: 00007ffe824ce610 RDI: 0000000000000005 RBP: 00007f54dd218a60 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007ffe824ce610 R14: 00007f54ddf54620 R15: 0000000000000003