INFO: task syz.2.784:14329 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.784 state:D stack:25352 pid:14329 tgid:14328 ppid:12302 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5388 [inline] __schedule+0x16ec/0x5620 kernel/sched/core.c:7189 __schedule_loop kernel/sched/core.c:7268 [inline] schedule+0x164/0x360 kernel/sched/core.c:7283 schedule_timeout+0xc3/0x2c0 kernel/time/sleep_timeout.c:75 do_wait_for_common kernel/sched/completion.c:100 [inline] __wait_for_common kernel/sched/completion.c:121 [inline] wait_for_common kernel/sched/completion.c:132 [inline] wait_for_completion+0x2cc/0x5e0 kernel/sched/completion.c:153 f2fs_issue_checkpoint+0x3e7/0x790 fs/f2fs/checkpoint.c:-1 f2fs_unlink+0x653/0xad0 fs/f2fs/namei.c:622 vfs_unlink+0x272/0x6d0 fs/namei.c:5498 filename_unlinkat+0x3d3/0x610 fs/namei.c:5568 __do_sys_unlink fs/namei.c:5603 [inline] __se_sys_unlink+0x2e/0x140 fs/namei.c:5600 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: 0033:0x7fc15bd9cdd9 RSP: 002b:00007fc159fee028 EFLAGS: 00000246 ORIG_RAX: 0000000000000057 RAX: ffffffffffffffda RBX: 00007fc15c015fa0 RCX: 00007fc15bd9cdd9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00002000000000c0 RBP: 00007fc15be32d69 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fc15c016038 R14: 00007fc15c015fa0 R15: 00007ffe54fabc38 Showing all locks held in the system: 1 lock held by khungtaskd/38: #0: ffffffff8dfc8140 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #0: ffffffff8dfc8140 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff8dfc8140 (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: ffff888032bed938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3277 [inline] #0: ffff888032bed938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3385 #1: ffffc90000b57c40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3278 [inline] #1: ffffc90000b57c40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3385 #2: ffffffff8f3574f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #2: ffffffff8f3574f8 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x124/0x1680 net/ipv6/addrconf.c:4206 3 locks held by kworker/0:2/820: #0: ffff88801a037938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3277 [inline] #0: ffff88801a037938 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3385 #1: ffffc9000513fc40 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3278 [inline] #1: ffffc9000513fc40 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3385 #2: ffff888038930280 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x222/0x3e0 drivers/net/netdevsim/fib.c:1490 3 locks held by kworker/u8:7/1130: #0: ffff88801f2af138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3277 [inline] #0: ffff88801f2af138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3385 #1: ffffc900060a7c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3278 [inline] #1: ffffc900060a7c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3385 #2: ffff888054f240d0 (&type->s_umount_key#53){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:565 6 locks held by kworker/u8:8/1365: #0: ffff88801b290938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3277 [inline] #0: ffff88801b290938 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3385 #1: ffffc90006427c40 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3278 [inline] #1: ffffc90006427c40 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3385 #2: ffffffff8f3487a0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf4/0x800 net/core/net_namespace.c:673 #3: ffff888066395160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1040 [inline] #3: ffff888066395160 (&dev->mutex){....}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:124 [inline] #3: ffff888066395160 (&dev->mutex){....}-{4:4}, at: devlink_pernet_pre_exit+0x129/0x420 net/devlink/core.c:555 #4: ffff888075546310 (&devlink->lock_key#44){+.+.}-{4:4}, at: devl_lock net/devlink/core.c:292 [inline] #4: ffff888075546310 (&devlink->lock_key#44){+.+.}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:125 [inline] #4: ffff888075546310 (&devlink->lock_key#44){+.+.}-{4:4}, at: devlink_pernet_pre_exit+0x142/0x420 net/devlink/core.c:555 #5: ffffffff8f3574f8 (rtnl_mutex){+.+.}-{4:4}, at: nsim_init_netdevsim drivers/net/netdevsim/netdev.c:1057 [inline] #5: ffffffff8f3574f8 (rtnl_mutex){+.+.}-{4:4}, at: nsim_create+0x894/0x1170 drivers/net/netdevsim/netdev.c:1151 2 locks held by getty/5354: #0: ffff8880294d00a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90003cc62e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13a0 drivers/tty/n_tty.c:2211 3 locks held by kworker/0:8/5817: #0: ffff88801a037938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3277 [inline] #0: ffff88801a037938 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3385 #1: ffffc90005bafc40 (rx_mode_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3278 [inline] #1: ffffc90005bafc40 (rx_mode_work){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3385 #2: ffffffff8f3574f8 (rtnl_mutex){+.+.}-{4:4}, at: netdev_rx_mode_work+0x1c/0x450 net/core/dev_addr_lists.c:1312 3 locks held by syz.2.784/14329: #0: ffff888054f24480 (sb_writers#12){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:493 #1: ffff888061bcf558 (&type->i_mutex_dir_key#8/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1074 [inline] #1: ffff888061bcf558 (&type->i_mutex_dir_key#8/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2914 [inline] #1: ffff888061bcf558 (&type->i_mutex_dir_key#8/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2938 [inline] #1: ffff888061bcf558 (&type->i_mutex_dir_key#8/1){+.+.}-{4:4}, at: filename_unlinkat+0x2ad/0x610 fs/namei.c:5549 #2: ffff888061b07558 (&sb->s_type->i_mutex_key#24){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1029 [inline] #2: ffff888061b07558 (&sb->s_type->i_mutex_key#24){+.+.}-{4:4}, at: vfs_unlink+0xed/0x6d0 fs/namei.c:5484 4 locks held by f2fs_ckpt-7:2/14359: 1 lock held by syz-executor/15292: #0: ffffffff8f3574f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff8f3574f8 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x404/0x1ad0 net/ipv4/devinet.c:978 2 locks held by syz-executor/15570: #0: ffffffff8f890bd8 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #0: ffffffff8f890bd8 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff8f890bd8 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570 #1: ffffffff8f3574f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #1: ffffffff8f3574f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #1: ffffffff8f3574f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x883/0x1bb0 net/core/rtnetlink.c:4109 2 locks held by syz-executor/15638: 1 lock held by syz.8.865/15652: #0: ffff88803991c0d0 (&type->s_umount_key#77){+.+.}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88803991c0d0 (&type->s_umount_key#77){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff88803991c0d0 (&type->s_umount_key#77){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 5 locks held by syz.1.866/15658: #0: ffff888037bc44b0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:592 [inline] #0: ffff888037bc44b0 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x194/0x9e0 mm/mmap.c:1284 #1: ffffffff8dfc8140 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #1: ffffffff8dfc8140 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #1: ffffffff8dfc8140 (rcu_read_lock){....}-{1:3}, at: __pte_offset_map+0x29/0x200 mm/pgtable-generic.c:290 #2: ffff88803b732c58 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline] #2: ffff88803b732c58 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: pte_offset_map_lock+0x13d/0x210 mm/pgtable-generic.c:404 #3: ffffffff8dfc8140 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #3: ffffffff8dfc8140 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #3: ffffffff8dfc8140 (rcu_read_lock){....}-{1:3}, at: __rt_spin_lock kernel/locking/spinlock_rt.c:50 [inline] #3: ffffffff8dfc8140 (rcu_read_lock){....}-{1:3}, at: rt_spin_lock+0x1e0/0x400 kernel/locking/spinlock_rt.c:57 #4: ffff8880b8833f10 ((lock)#2){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline] #4: ffff8880b8833f10 ((lock)#2){+.+.}-{3:3}, at: __lru_cache_activate_folio+0x144/0x5a0 mm/swap.c:366 9 locks held by udevadm/15684: 4 locks held by dhcpcd-run-hook/15686: ============================================= 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 04/18/2026 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:162 [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+0xfd3/0x1030 kernel/hung_task.c:561 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: 14359 Comm: f2fs_ckpt-7:2 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 RIP: 0010:__lock_acquire+0x82/0x2cf0 kernel/locking/lockdep.c:5103 Code: 8b 0d 72 0e 49 0c 85 c9 44 0f 44 c1 31 c9 48 3d 30 53 2e 93 41 0f 45 c8 89 4c 24 10 8b 0d b6 9e d5 17 85 c9 0f 95 c0 83 fe 08 <0f> 92 c2 08 c2 0f 84 49 01 00 00 83 fe 01 77 0c 89 f0 49 8b 44 c1 RSP: 0018:ffffc900064c7558 EFLAGS: 00000093 RAX: ffffffff997a0b00 RBX: ffffc900064c76f4 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8dfc8140 RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff8dfc8140 R10: 0000000000000000 R11: ffffed100c360ec3 R12: 0000000000000005 R13: 0000000000000002 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff888126276000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fdc54d1d286 CR3: 0000000038d1a000 CR4: 00000000003526f0 Call Trace: reacquire_held_locks+0x104/0x190 kernel/locking/lockdep.c:5385 __lock_release kernel/locking/lockdep.c:5574 [inline] lock_release+0x199/0x3c0 kernel/locking/lockdep.c:5889 rt_spin_unlock+0x29/0x200 kernel/locking/spinlock_rt.c:80 spin_unlock include/linux/spinlock_rt.h:109 [inline] igrab+0x13d/0x1e0 fs/inode.c:-1 f2fs_sync_inode_meta fs/f2fs/checkpoint.c:1347 [inline] block_operations fs/f2fs/checkpoint.c:1461 [inline] f2fs_write_checkpoint+0xb73/0x26a0 fs/f2fs/checkpoint.c:1876 __write_checkpoint_sync+0x124/0x2b0 fs/f2fs/checkpoint.c:2003 __checkpoint_and_complete_reqs+0x53/0x2d0 fs/f2fs/checkpoint.c:2022 issue_checkpoint_thread+0xd6/0x280 fs/f2fs/checkpoint.c:2054 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