INFO: task syz.1.1088:14327 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.1088 state:D stack:24664 pid:14327 tgid:14325 ppid:13415 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x1681/0x54c0 kernel/sched/core.c:7183 __schedule_loop kernel/sched/core.c:7262 [inline] rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7558 rt_mutex_slowlock_block kernel/locking/rtmutex.c:1659 [inline] __rt_mutex_slowlock kernel/locking/rtmutex.c:1736 [inline] __rt_mutex_slowlock_locked+0x1f8f/0x25c0 kernel/locking/rtmutex.c:1776 rt_mutex_slowlock+0xbd/0x170 kernel/locking/rtmutex.c:1816 __rt_mutex_lock kernel/locking/rtmutex.c:1831 [inline] rwbase_write_lock+0x14d/0x730 kernel/locking/rwbase_rt.c:245 inode_lock include/linux/fs.h:1029 [inline] open_last_lookups fs/namei.c:4608 [inline] path_openat+0xb5e/0x38a0 fs/namei.c:4855 do_file_open+0x23e/0x4a0 fs/namei.c:4887 do_sys_openat2+0x113/0x200 fs/open.c:1364 do_sys_open fs/open.c:1370 [inline] __do_sys_openat fs/open.c:1386 [inline] __se_sys_openat fs/open.c:1381 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1381 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f918879c819 RSP: 002b:00007f91869d5028 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f9188a16090 RCX: 00007f918879c819 RDX: 0000000000183042 RSI: 0000200000000200 RDI: ffffffffffffff9c RBP: 00007f9188832c91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000015 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f9188a16128 R14: 00007f9188a16090 R15: 00007ffe84a2e528 Showing all locks held in the system: 1 lock held by khungtaskd/37: #0: ffffffff8dfc7e40 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #0: ffffffff8dfc7e40 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff8dfc7e40 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 3 locks held by kworker/u8:6/155: #0: ffff88801cb92938 ((wq_completion)cfg80211){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3277 [inline] #0: ffff88801cb92938 ((wq_completion)cfg80211){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3385 #1: ffffc900039b7c40 ((work_completion)(&(&rdev->dfs_update_channels_wk)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3278 [inline] #1: ffffc900039b7c40 ((work_completion)(&(&rdev->dfs_update_channels_wk)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3385 #2: ffffffff8f35ffb8 (rtnl_mutex){+.+.}-{4:4}, at: cfg80211_dfs_channels_update_work+0xd6/0x660 net/wireless/mlme.c:1045 3 locks held by kworker/u8:11/1665: #0: ffff888032c7f938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3277 [inline] #0: ffff888032c7f938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3385 #1: ffffc90006d7fc40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3278 [inline] #1: ffffc90006d7fc40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3385 #2: ffffffff8f35ffb8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #2: ffffffff8f35ffb8 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x124/0x1680 net/ipv6/addrconf.c:4206 2 locks held by dhcpcd/5460: #0: ffff888066b4a928 (nlk_cb_mutex-ROUTE){+.+.}-{4:4}, at: netlink_dump+0xe2/0xe10 net/netlink/af_netlink.c:2267 #1: ffffffff8f35ffb8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #1: ffffffff8f35ffb8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_dumpit+0x92/0x200 net/core/rtnetlink.c:6862 2 locks held by getty/5553: #0: ffff888033cd90a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90003cbe2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13a0 drivers/tty/n_tty.c:2211 4 locks held by kworker/u8:8/8960: #0: ffff88801b2a0938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3277 [inline] #0: ffff88801b2a0938 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3385 #1: ffffc90004027c40 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3278 [inline] #1: ffffc90004027c40 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3385 #2: ffffffff8f3516c0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf4/0x800 net/core/net_namespace.c:673 #3: ffffffff8f35ffb8 (rtnl_mutex){+.+.}-{4:4}, at: wiphy_unregister+0x26a/0xb00 net/wireless/core.c:1254 4 locks held by kworker/u8:10/11174: #0: ffff88801f2f6938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3277 [inline] #0: ffff88801f2f6938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3385 #1: ffffc90003b17c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3278 [inline] #1: ffffc90003b17c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3385 #2: ffff888011fca0d0 (&type->s_umount_key#57){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:565 #3: ffff8880398a4580 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x1ca/0x530 fs/jfs/inode.c:108 4 locks held by syz.1.1088/14326: 2 locks held by syz.1.1088/14327: #0: ffff888011fca480 (sb_writers#14){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:493 #1: ffff8880398a4950 (&type->i_mutex_dir_key#19){++++}-{4:4}, at: inode_lock include/linux/fs.h:1029 [inline] #1: ffff8880398a4950 (&type->i_mutex_dir_key#19){++++}-{4:4}, at: open_last_lookups fs/namei.c:4608 [inline] #1: ffff8880398a4950 (&type->i_mutex_dir_key#19){++++}-{4:4}, at: path_openat+0xb5e/0x38a0 fs/namei.c:4855 1 lock held by syz-executor/15560: #0: ffffffff8f35ffb8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #0: ffffffff8f35ffb8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #0: ffffffff8f35ffb8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x883/0x1bb0 net/core/rtnetlink.c:4107 7 locks held by syz-executor/15786: 4 locks held by syz-executor/15876: #0: ffff888035764480 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2731 [inline] #0: ffff888035764480 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x22d/0xba0 fs/read_write.c:684 #1: ffff8880112c8c78 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1df/0x540 fs/kernfs/file.c:343 #2: ffff888028f60878 (kn->active#52){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline] #2: ffff888028f60878 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x232/0x540 fs/kernfs/file.c:344 #3: ffffffff8ebc88f8 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd7/0x370 drivers/net/netdevsim/bus.c:234 2 locks held by syz-executor/15882: #0: ffffffff8f8b2a58 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #0: ffffffff8f8b2a58 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff8f8b2a58 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570 #1: ffffffff8f35ffb8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #1: ffffffff8f35ffb8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #1: ffffffff8f35ffb8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x883/0x1bb0 net/core/rtnetlink.c:4107 2 locks held by syz-executor/15897: #0: ffffffff8f8cfe68 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #0: ffffffff8f8cfe68 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff8f8cfe68 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570 #1: ffffffff8f35ffb8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #1: ffffffff8f35ffb8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #1: ffffffff8f35ffb8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x883/0x1bb0 net/core/rtnetlink.c:4107 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 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+0xfaa/0x1000 kernel/hung_task.c:515 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 14326 Comm: syz.1.1088 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 RIP: 0010:check_kcov_mode kernel/kcov.c:183 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x2a/0x80 kernel/kcov.c:217 Code: f3 0f 1e fa 48 8b 04 24 65 48 8b 0d 28 14 ac 10 65 8b 35 49 14 ac 10 81 e6 00 00 ff 00 ba 00 01 00 00 23 91 e4 0b 00 00 89 d7 <09> f7 74 11 85 f6 75 39 85 d2 74 35 83 b9 b4 16 00 00 00 74 2c 8b RSP: 0018:ffffc900049476a0 EFLAGS: 00000246 RAX: ffffffff83515c6f RBX: 0000000000000004 RCX: ffff888027665c40 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0030000000000000 R11: 000007ff00000020 R12: dffffc0000000000 R13: ffff8880618cb000 R14: 0000000000000000 R15: 1ffff1100c319602 FS: 00007f91869f66c0(0000) GS:ffff888126224000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000562442162000 CR3: 000000002a132000 CR4: 00000000003526f0 Call Trace: dtSplitRoot+0x77f/0x16c0 fs/jfs/jfs_dtree.c:1979 dtSplitUp fs/jfs/jfs_dtree.c:993 [inline] dtInsert+0xf19/0x5f10 fs/jfs/jfs_dtree.c:871 jfs_mknod+0x6bd/0x9d0 fs/jfs/namei.c:1413 vfs_mknod+0x44e/0x620 fs/namei.c:5120 filename_mknodat+0x3cf/0x670 fs/namei.c:-1 __do_sys_mknod fs/namei.c:5207 [inline] __se_sys_mknod+0x3a/0x150 fs/namei.c:5204 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f918879c819 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f91869f6028 EFLAGS: 00000246 ORIG_RAX: 0000000000000085 RAX: ffffffffffffffda RBX: 00007f9188a15fa0 RCX: 00007f918879c819 RDX: 0000000000000702 RSI: 0000000000006000 RDI: 0000200000000380 RBP: 00007f9188832c91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f9188a16038 R14: 00007f9188a15fa0 R15: 00007ffe84a2e528