INFO: task syz.5.356:11114 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.5.356 state:D stack:26384 pid:11114 tgid:11113 ppid:10311 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5533 [inline] __schedule+0x16d9/0x5700 kernel/sched/core.c:7284 __schedule_loop kernel/sched/core.c:7361 [inline] rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7668 rt_mutex_slowlock_block kernel/locking/rtmutex.c:1670 [inline] __rt_mutex_slowlock kernel/locking/rtmutex.c:1747 [inline] __rt_mutex_slowlock_locked+0x1f88/0x25b0 kernel/locking/rtmutex.c:1787 __rwbase_read_lock+0xc3/0x190 kernel/locking/rwbase_rt.c:114 rwbase_read_lock kernel/locking/rwbase_rt.c:147 [inline] __down_read kernel/locking/rwsem.c:1502 [inline] down_read+0x132/0x200 kernel/locking/rwsem.c:1576 __super_lock fs/super.c:62 [inline] super_lock+0x2d6/0x3d0 fs/super.c:124 __iterate_supers+0x26b/0x420 fs/super.c:980 drop_caches_sysctl_handler+0x97/0x170 fs/drop_caches.c:64 proc_sys_call_handler+0x4c7/0x830 fs/proc/proc_sysctl.c:600 new_sync_write fs/read_write.c:595 [inline] vfs_write+0x61e/0xbb0 fs/read_write.c:687 ksys_write+0x156/0x270 fs/read_write.c:739 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f8e7c5ee159 RSP: 002b:00007f8e7a846028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f8e7c875fa0 RCX: 00007f8e7c5ee159 RDX: 0000000000000001 RSI: 00002000000006c0 RDI: 0000000000000004 RBP: 00007f8e7c68506b R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f8e7c876038 R14: 00007f8e7c875fa0 R15: 00007ffec91f5548 Showing all locks held in the system: locks held by rcuc/1/28: 3, last CPU#1: #0: ffffffff8e059540 (local_bh){.+.+}-{1:3}, at: __local_bh_disable_ip+0x3d/0x420 kernel/softirq.c:186 #1: ffffffff8e1c3cc0 (rcu_read_lock){....}-{1:3}, at: __local_bh_disable_ip+0x3d/0x420 kernel/softirq.c:186 #2: ffffffff8e1c3de0 (rcu_callback){....}-{0:0}, at: local_bh_disable include/linux/bottom_half.h:20 [inline] #2: ffffffff8e1c3de0 (rcu_callback){....}-{0:0}, at: rcu_cpu_kthread+0x217/0x1740 kernel/rcu/tree.c:3000 locks held by khungtaskd/37: 1, last CPU#0: #0: ffffffff8e1c3cc0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #0: ffffffff8e1c3cc0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e1c3cc0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6871 locks held by kworker/u8:2/47: 5, last CPU#0: #0: ffff88801aeb0938 ((wq_completion)netns){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #0: ffff88801aeb0938 ((wq_completion)netns){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffff88801aeb0938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline] #0: ffff88801aeb0938 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479 #1: ffffc90000b97c40 (net_cleanup_work){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #1: ffffc90000b97c40 (net_cleanup_work){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #1: ffffc90000b97c40 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline] #1: ffffc90000b97c40 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479 #2: ffffffff8f5c67a0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf5/0x810 net/core/net_namespace.c:677 #3: ffffffff8e059540 (local_bh){.+.+}-{1:3}, at: __local_bh_disable_ip+0x3d/0x420 kernel/softirq.c:186 #4: ffffffff8e1c3cc0 (rcu_read_lock){....}-{1:3}, at: __local_bh_disable_ip+0x3d/0x420 kernel/softirq.c:186 locks held by kworker/u8:6/165: 2, last CPU#0: #0: ffff88806bade938 ((wq_completion)bond0#47){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #0: ffff88806bade938 ((wq_completion)bond0#47){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffff88806bade938 ((wq_completion)bond0#47){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline] #0: ffff88806bade938 ((wq_completion)bond0#47){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479 #1: ffffc9000154fc40 ((work_completion)(&(&slave->notify_work)->work)){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #1: ffffc9000154fc40 ((work_completion)(&(&slave->notify_work)->work)){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #1: ffffc9000154fc40 ((work_completion)(&(&slave->notify_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline] #1: ffffc9000154fc40 ((work_completion)(&(&slave->notify_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479 locks held by kworker/u8:9/1175: 3, on CPU#1: #0: ffff888032625138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #0: ffff888032625138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffff888032625138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline] #0: ffff888032625138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479 #1: ffffc90006807c40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #1: ffffc90006807c40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #1: ffffc90006807c40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline] #1: ffffc90006807c40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479 #2: ffffffff8f5d4ff8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:134 [inline] #2: ffffffff8f5d4ff8 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x123/0x16e0 net/ipv6/addrconf.c:4230 locks held by kworker/u8:11/1842: 3, last CPU#0: #0: ffff888032d1b938 ((wq_completion)bat_events){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #0: ffff888032d1b938 ((wq_completion)bat_events){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffff888032d1b938 ((wq_completion)bat_events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline] #0: ffff888032d1b938 ((wq_completion)bat_events){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479 #1: ffffc900074f7c40 ((work_completion)(&(&bat_priv->dat.work)->work)){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #1: ffffc900074f7c40 ((work_completion)(&(&bat_priv->dat.work)->work)){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #1: ffffc900074f7c40 ((work_completion)(&(&bat_priv->dat.work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline] #1: ffffc900074f7c40 ((work_completion)(&(&bat_priv->dat.work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479 #2: ffffffff8e059540 (local_bh){.+.+}-{1:3}, at: __local_bh_disable_ip+0x3d/0x420 kernel/softirq.c:186 locks held by dhcpcd/5251: 2, on CPU#0: #0: ffffffff8f5b6098 (vlan_ioctl_mutex){+.+.}-{4:4}, at: sock_ioctl+0x5ee/0x7f0 net/socket.c:1408 #1: ffffffff8f5d4ff8 (rtnl_mutex){+.+.}-{4:4}, at: vlan_ioctl_handler+0xf0/0x630 net/8021q/vlan.c:519 locks held by getty/5346: 2, on CPU#0: #0: ffff888035a980a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900044d62e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x460/0x1360 drivers/tty/n_tty.c:2211 locks held by kworker/1:3/5710: 3, on CPU#1: #0: ffff88813ff27938 ((wq_completion)events){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #0: ffff88813ff27938 ((wq_completion)events){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffff88813ff27938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline] #0: ffff88813ff27938 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479 #1: ffffc90005c1fc40 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #1: ffffc90005c1fc40 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #1: ffffc90005c1fc40 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline] #1: ffffc90005c1fc40 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479 #2: ffff88803016a280 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x222/0x3e0 drivers/net/netdevsim/fib.c:1490 locks held by syz-executor/8952: 4, last CPU#1: #0: ffff888031d560e0 (&type->s_umount_key#57){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #0: ffff888031d560e0 (&type->s_umount_key#57){++++}-{4:4}, at: __super_lock_excl fs/super.c:75 [inline] #0: ffff888031d560e0 (&type->s_umount_key#57){++++}-{4:4}, at: deactivate_super+0xac/0xe0 fs/super.c:617 #1: ffff888060d08350 (&sbi->cp_global_sem_key){+.+.}-{4:4}, at: f2fs_down_write fs/f2fs/f2fs.h:2469 [inline] #1: ffff888060d08350 (&sbi->cp_global_sem_key){+.+.}-{4:4}, at: f2fs_down_write_trace+0x34/0x1f0 fs/f2fs/checkpoint.c:181 #2: ffff888060d083e8 (&sbi->cp_rwsem){++++}-{4:4}, at: spin_lock include/linux/spinlock_rt.h:45 [inline] #2: ffff888060d083e8 (&sbi->cp_rwsem){++++}-{4:4}, at: f2fs_sync_inode_meta fs/f2fs/checkpoint.c:1451 [inline] #2: ffff888060d083e8 (&sbi->cp_rwsem){++++}-{4:4}, at: block_operations fs/f2fs/checkpoint.c:1572 [inline] #2: ffff888060d083e8 (&sbi->cp_rwsem){++++}-{4:4}, at: f2fs_write_checkpoint+0xb98/0x2710 fs/f2fs/checkpoint.c:1987 #3: ffff888060d083a8 (_T->lock){....}-{2:2}, at: rt_mutex_slowunlock+0xbf/0xa30 kernel/locking/rtmutex.c:1430 locks held by syz.5.356/11114: 3, on CPU#1: #0: ffff8880318c4328 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x252/0x320 fs/file.c:1259 #1: ffff88801bbe4510 (sb_writers#3){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2753 [inline] #1: ffff88801bbe4510 (sb_writers#3){.+.+}-{0:0}, at: vfs_write+0x231/0xbb0 fs/read_write.c:683 #2: ffff888031d560e0 (&type->s_umount_key#57){++++}-{4:4}, at: __super_lock fs/super.c:62 [inline] #2: ffff888031d560e0 (&type->s_umount_key#57){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:124 locks held by syz-executor/11945: 1, on CPU#1: #0: ffffffff8f5d4ff8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:134 [inline] #0: ffffffff8f5d4ff8 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x470/0x19f0 net/ipv4/devinet.c:978 locks held by syz-executor/11951: 1, on CPU#1: #0: ffffffff8f5d4ff8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:134 [inline] #0: ffffffff8f5d4ff8 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x470/0x19f0 net/ipv4/devinet.c:978 locks held by syz-executor/12149: 2, on CPU#1: #0: ffffffff8fb3e388 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #0: ffffffff8fb3e388 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8fb3e388 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:595 #1: ffffffff8f5d4ff8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #1: ffffffff8f5d4ff8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:366 [inline] #1: ffffffff8f5d4ff8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0xc10/0x1c30 net/core/rtnetlink.c:4219 locks held by syz-executor/12155: 1, last CPU#0: #0: ffffffff8f5d4ff8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #0: ffffffff8f5d4ff8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:366 [inline] #0: ffffffff8f5d4ff8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0xc10/0x1c30 net/core/rtnetlink.c:4219 locks held by syz-executor/12182: 1, on CPU#1: #0: ffffffff8f5d4ff8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #0: ffffffff8f5d4ff8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:366 [inline] #0: ffffffff8f5d4ff8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0xc10/0x1c30 net/core/rtnetlink.c:4219 ============================================= 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 07/24/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:123 nmi_trigger_cpumask_backtrace+0x17d/0x390 lib/nmi_backtrace.c:66 trigger_all_cpu_backtrace include/linux/nmi.h:164 [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:353 [inline] watchdog+0xfd7/0x1030 kernel/hung_task.c:561 kthread+0x38b/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: 8952 Comm: syz-executor Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 RIP: 0010:rcu_lockdep_current_cpu_online+0x62/0x120 kernel/rcu/tree.c:4116 Code: 09 89 c3 83 f8 08 0f 83 c8 00 00 00 49 be 00 00 00 00 00 fc ff df 48 8d 1c dd d0 77 b2 8d 48 89 d8 48 c1 e8 03 42 80 3c 30 00 <74> 08 48 89 df e8 54 26 87 00 48 8b 03 48 8d 98 40 53 a7 92 48 8d RSP: 0018:ffffc90005f8f448 EFLAGS: 00000246 RAX: 1ffffffff1b64efb RBX: ffffffff8db277d8 RCX: 8000000000000001 RDX: 0000000000000000 RSI: ffffffff8bcc4560 RDI: ffffffff8bcc4520 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: ffffc90005f8f580 R11: fffff52000bf1eb3 R12: ffff888061bd6340 R13: ffffc90005f8f578 R14: dffffc0000000000 R15: 1ffff92000bf1eaf FS: 0000555578b64500(0000) GS:ffff888125cc8000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffc2db7ff20 CR3: 0000000059cc6000 CR4: 00000000003526f0 Call Trace: rcu_read_lock_held_common kernel/rcu/update.c:113 [inline] rcu_read_lock_held+0x1e/0x50 kernel/rcu/update.c:349 xa_head include/linux/xarray.h:1210 [inline] xas_start+0x29b/0x780 lib/xarray.c:191 xas_load+0x2c/0x5a0 lib/xarray.c:239 filemap_get_entry+0x181/0x3f0 mm/filemap.c:1907 __filemap_get_folio_mpol+0x3c/0xf50 mm/filemap.c:1953 __filemap_get_folio include/linux/pagemap.h:761 [inline] f2fs_grab_cache_folio fs/f2fs/f2fs.h:3109 [inline] __get_node_folio+0x20e/0xd90 fs/f2fs/node.c:1593 f2fs_update_inode_page+0x9d/0x360 fs/f2fs/inode.c:801 f2fs_sync_inode_meta fs/f2fs/checkpoint.c:1465 [inline] block_operations fs/f2fs/checkpoint.c:1572 [inline] f2fs_write_checkpoint+0xc4c/0x2710 fs/f2fs/checkpoint.c:1987 kill_f2fs_super+0x2dd/0x700 fs/f2fs/super.c:5665 deactivate_locked_super+0xbc/0x110 fs/super.c:589 cleanup_mnt+0x3d3/0x460 fs/namespace.c:1317 task_work_run+0x1d9/0x270 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:70 [inline] exit_to_user_mode_loop+0x204/0x770 kernel/entry/common.c:101 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:343 [inline] do_syscall_64+0x328/0x520 arch/x86/entry/syscall_64.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f3a504df397 Code: a2 c7 05 5c 43 25 00 00 00 00 00 eb 96 e8 e1 12 00 00 90 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 b8 RSP: 002b:00007fff8a347618 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007f3a505744bb RCX: 00007f3a504df397 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007fff8a3476d0 RBP: 00007fff8a3476d0 R08: 00007fff8a3486d0 R09: 00000000ffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 00007fff8a348760 R13: 00007f3a505744bb R14: 0000000000075638 R15: 00007fff8a3487a0