INFO: task syz.2.8:5938 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.8 state:D stack:25096 pid:5938 tgid:5937 ppid:5801 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5298 [inline] __schedule+0x1553/0x5240 kernel/sched/core.c:6911 __schedule_loop kernel/sched/core.c:6993 [inline] schedule+0x164/0x360 kernel/sched/core.c:7008 io_schedule+0x80/0xe0 kernel/sched/core.c:7835 folio_wait_bit_common+0x6dd/0xbc0 mm/filemap.c:1323 folio_lock include/linux/pagemap.h:1159 [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 dtSearch+0x591/0x21b0 fs/jfs/jfs_dtree.c:624 jfs_lookup+0x1b0/0x420 fs/jfs/namei.c:1464 __lookup_slow+0x2d2/0x440 fs/namei.c:1916 lookup_slow+0x53/0x70 fs/namei.c:1933 walk_component fs/namei.c:2279 [inline] lookup_last fs/namei.c:2786 [inline] path_lookupat+0x3f5/0x8c0 fs/namei.c:2810 filename_lookup+0x256/0x5d0 fs/namei.c:2839 __do_sys_chdir fs/open.c:559 [inline] __se_sys_chdir+0xa8/0x2a0 fs/open.c:552 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fa079b8c819 RSP: 002b:00007fa077de6028 EFLAGS: 00000246 ORIG_RAX: 0000000000000050 RAX: ffffffffffffffda RBX: 00007fa079e05fa0 RCX: 00007fa079b8c819 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000200000000000 RBP: 00007fa079c22c91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fa079e06038 R14: 00007fa079e05fa0 R15: 00007fff626a0738 INFO: task syz.2.8:5989 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.8 state:D stack:25624 pid:5989 tgid:5937 ppid:5801 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5298 [inline] __schedule+0x1553/0x5240 kernel/sched/core.c:6911 __schedule_loop kernel/sched/core.c:6993 [inline] rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7289 rwbase_write_lock+0x3da/0x730 kernel/locking/rwbase_rt.c:272 inode_lock include/linux/fs.h:1028 [inline] open_last_lookups fs/namei.c:4586 [inline] path_openat+0xb5e/0x38a0 fs/namei.c:4833 do_file_open+0x23e/0x4a0 fs/namei.c:4865 do_sys_openat2+0x113/0x200 fs/open.c:1366 do_sys_open fs/open.c:1372 [inline] __do_sys_openat fs/open.c:1388 [inline] __se_sys_openat fs/open.c:1383 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1383 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fa079b8c819 RSP: 002b:00007fa077dc5028 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007fa079e06090 RCX: 00007fa079b8c819 RDX: 000000000000275a RSI: 00002000000000c0 RDI: ffffffffffffff9c RBP: 00007fa079c22c91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fa079e06128 R14: 00007fa079e06090 R15: 00007fff626a0738 INFO: task syz.2.8:6001 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.8 state:D stack:26688 pid:6001 tgid:5937 ppid:5801 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5298 [inline] __schedule+0x1553/0x5240 kernel/sched/core.c:6911 __schedule_loop kernel/sched/core.c:6993 [inline] rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7289 rt_mutex_slowlock_block kernel/locking/rtmutex.c:1647 [inline] __rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline] __rt_mutex_slowlock_locked+0x1f8f/0x25c0 kernel/locking/rtmutex.c:1760 rt_mutex_slowlock+0xbd/0x170 kernel/locking/rtmutex.c:1800 __rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline] rwbase_write_lock+0x14d/0x730 kernel/locking/rwbase_rt.c:244 inode_lock include/linux/fs.h:1028 [inline] open_last_lookups fs/namei.c:4586 [inline] path_openat+0xb5e/0x38a0 fs/namei.c:4833 do_file_open+0x23e/0x4a0 fs/namei.c:4865 do_sys_openat2+0x113/0x200 fs/open.c:1366 do_sys_open fs/open.c:1372 [inline] __do_sys_openat fs/open.c:1388 [inline] __se_sys_openat fs/open.c:1383 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1383 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fa079b8c819 RSP: 002b:00007fa077981028 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007fa079e06270 RCX: 00007fa079b8c819 RDX: 00000000000c4042 RSI: 0000200000000300 RDI: ffffffffffffff9c RBP: 00007fa079c22c91 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000000001ff R11: 0000000000000246 R12: 0000000000000000 R13: 00007fa079e06308 R14: 00007fa079e06270 R15: 00007fff626a0738 Showing all locks held in the system: 3 locks held by kworker/u8:1/13: #0: ffff88801f2be938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3263 [inline] #0: ffff88801f2be938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0 kernel/workqueue.c:3371 #1: ffffc90000127c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3264 [inline] #1: ffffc90000127c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0 kernel/workqueue.c:3371 #2: ffff888038dcc0d0 (&type->s_umount_key#74){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:565 6 locks held by ktimers/0/16: 1 lock held by khungtaskd/38: #0: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 3 locks held by kworker/u8:2/43: #0: ffff888019c44138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3263 [inline] #0: ffff888019c44138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0 kernel/workqueue.c:3371 #1: ffffc90000b57c40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3264 [inline] #1: ffffc90000b57c40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0 kernel/workqueue.c:3371 #2: ffffffff8f15d578 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:313 3 locks held by kworker/u8:3/57: #0: ffff88803276c138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3263 [inline] #0: ffff88803276c138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0 kernel/workqueue.c:3371 #1: ffffc9000123fc40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3264 [inline] #1: ffffc9000123fc40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0 kernel/workqueue.c:3371 #2: ffffffff8f15d578 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #2: ffffffff8f15d578 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x124/0x1680 net/ipv6/addrconf.c:4198 9 locks held by kworker/u8:5/116: 2 locks held by kworker/u8:12/4153: #0: ffff888019c44138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3263 [inline] #0: ffff888019c44138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0 kernel/workqueue.c:3371 #1: ffffc9001023fc40 (connector_reaper_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3264 [inline] #1: ffffc9001023fc40 (connector_reaper_work){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0 kernel/workqueue.c:3371 2 locks held by dhcpcd/5458: #0: ffff88806426e928 (nlk_cb_mutex-ROUTE){+.+.}-{4:4}, at: __netlink_dump_start+0xfe/0x7e0 net/netlink/af_netlink.c:2404 #1: ffffffff8f15d578 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #1: ffffffff8f15d578 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_dumpit+0x92/0x200 net/core/rtnetlink.c:6862 2 locks held by getty/5552: #0: ffff888037c4f0a0 (&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 2 locks held by syz-executor/5796: 1 lock held by udevd/5858: 1 lock held by syz.2.8/5938: #0: ffff88806170c038 (&type->i_mutex_dir_key#14){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:1043 [inline] #0: ffff88806170c038 (&type->i_mutex_dir_key#14){++++}-{4:4}, at: lookup_slow+0x46/0x70 fs/namei.c:1932 1 lock held by syz.2.8/5989: #0: ffff88806170c038 (&type->i_mutex_dir_key#14){++++}-{4:4}, at: inode_lock include/linux/fs.h:1028 [inline] #0: ffff88806170c038 (&type->i_mutex_dir_key#14){++++}-{4:4}, at: open_last_lookups fs/namei.c:4586 [inline] #0: ffff88806170c038 (&type->i_mutex_dir_key#14){++++}-{4:4}, at: path_openat+0xb5e/0x38a0 fs/namei.c:4833 1 lock held by syz.2.8/6001: #0: ffff88806170c038 (&type->i_mutex_dir_key#14){++++}-{4:4}, at: inode_lock include/linux/fs.h:1028 [inline] #0: ffff88806170c038 (&type->i_mutex_dir_key#14){++++}-{4:4}, at: open_last_lookups fs/namei.c:4586 [inline] #0: ffff88806170c038 (&type->i_mutex_dir_key#14){++++}-{4:4}, at: path_openat+0xb5e/0x38a0 fs/namei.c:4833 1 lock held by syz-executor/7795: #0: ffffffff8f15d578 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff8f15d578 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x404/0x1ad0 net/ipv4/devinet.c:978 1 lock held by syz-executor/8040: #0: ffffffff8f15d578 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #0: ffffffff8f15d578 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #0: ffffffff8f15d578 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x883/0x1bb0 net/core/rtnetlink.c:4107 2 locks held by syz-executor/8173: #0: ffffffff8f14ede0 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x4f7/0x730 net/core/net_namespace.c:575 #1: ffffffff8f15d578 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock_killable include/linux/rtnetlink.h:145 [inline] #1: ffffffff8f15d578 (rtnl_mutex){+.+.}-{4:4}, at: register_netdev+0x18/0x60 net/core/dev.c:11554 5 locks held by syz.7.294/8224: ============================================= 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 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+0xfd9/0x1030 kernel/hung_task.c:515 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 116 Comm: kworker/u8:5 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 Workqueue: netns cleanup_net RIP: 0010:arch_stack_walk+0x96/0x150 arch/x86/kernel/stacktrace.c:18 Code: 89 e9 48 c7 45 d0 00 00 00 00 48 c7 45 c8 00 00 00 00 48 c7 45 c0 00 00 00 00 48 c7 45 b8 00 00 00 00 48 c7 45 b0 00 00 00 00 <48> c7 45 a8 00 00 00 00 48 c7 45 a0 00 00 00 00 48 c7 45 98 00 00 RSP: 0018:ffffc90003176948 EFLAGS: 00000246 RAX: ffff88801db3bd00 RBX: ffffc90003176a00 RCX: ffffc900031769d0 RDX: ffff88801db3bd00 RSI: ffffc90003176a00 RDI: ffffffff81af8da0 RBP: ffffc900031769d0 R08: ffffffff8178466c R09: 0000000000000000 R10: ffffc90003176a80 R11: fffffbfff1ed4f17 R12: ffff88801db3bd00 R13: dffffc0000000000 R14: ffffffff81af8da0 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff888126332000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555590bf84e8 CR3: 0000000044502000 CR4: 00000000003526f0 Call Trace: 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:3131 [inline] call_rcu+0xee/0x890 kernel/rcu/tree.c:3251 call_rcu_hurry include/linux/rcupdate.h:125 [inline] fib6_info_release include/net/ip6_fib.h:344 [inline] fib6_del_route net/ipv6/ip6_fib.c:2067 [inline] fib6_del+0x113a/0x15a0 net/ipv6/ip6_fib.c:2100 fib6_clean_node+0x29c/0x580 net/ipv6/ip6_fib.c:2262 fib6_walk_continue+0x67b/0x910 net/ipv6/ip6_fib.c:2184 fib6_walk net/ipv6/ip6_fib.c:2232 [inline] fib6_clean_tree net/ipv6/ip6_fib.c:2312 [inline] __fib6_clean_all+0x3aa/0x610 net/ipv6/ip6_fib.c:2328 rt6_sync_down_dev net/ipv6/route.c:5012 [inline] rt6_disable_ip+0x11f/0x750 net/ipv6/route.c:5017 addrconf_ifdown+0x157/0x1aa0 net/ipv6/addrconf.c:3857 addrconf_notify+0x1bc/0x1050 net/ipv6/addrconf.c:-1 notifier_call_chain+0x1be/0x400 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2287 [inline] call_netdevice_notifiers net/core/dev.c:2301 [inline] netif_close_many+0x2ae/0x420 net/core/dev.c:1804 unregister_netdevice_many_notify+0xb47/0x2360 net/core/dev.c:12401 unregister_netdevice_many net/core/dev.c:12494 [inline] default_device_exit_batch+0x981/0xa00 net/core/dev.c:13086 ops_exit_list net/core/net_namespace.c:205 [inline] ops_undo_list+0x52b/0x940 net/core/net_namespace.c:252 cleanup_net+0x56e/0x800 net/core/net_namespace.c:702 process_one_work kernel/workqueue.c:3288 [inline] process_scheduled_works+0xb6e/0x18c0 kernel/workqueue.c:3371 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3452 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245