INFO: task segctord:7286 blocked for more than 153 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:segctord state:D stack:28680 pid:7286 tgid:7286 ppid:2 task_flags:0x200040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5387 [inline] __schedule+0x17b4/0x5680 kernel/sched/core.c:7188 __schedule_loop kernel/sched/core.c:7267 [inline] schedule+0x164/0x360 kernel/sched/core.c:7282 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7339 rwsem_down_write_slowpath+0x883/0x1080 kernel/locking/rwsem.c:1215 __down_write_common kernel/locking/rwsem.c:1347 [inline] __down_write kernel/locking/rwsem.c:1356 [inline] down_write+0x1bc/0x200 kernel/locking/rwsem.c:1626 nilfs_transaction_lock+0x252/0x4c0 fs/nilfs2/segment.c:357 nilfs_segctor_thread_construct fs/nilfs2/segment.c:2569 [inline] nilfs_segctor_thread+0x6b5/0xdc0 fs/nilfs2/segment.c:2684 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 Showing all locks held in the system: 3 locks held by kworker/u8:0/12: #0: ffff8880b863aea0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xb6/0x150 kernel/sched/core.c:660 #1: ffff8880b8724588 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880 kernel/sched/psi.c:933 #2: ffff8880b8726118 (&base->lock){-.-.}-{2:2}, at: lock_timer_base kernel/time/timer.c:1004 [inline] #2: ffff8880b8726118 (&base->lock){-.-.}-{2:2}, at: __mod_timer+0x1ae/0xf30 kernel/time/timer.c:1085 1 lock held by khungtaskd/31: #0: ffffffff8e95cd60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #0: ffffffff8e95cd60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff8e95cd60 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 1 lock held by dhcpcd/5281: #0: ffffffff8fdce8c0 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff8fdce8c0 (rtnl_mutex){+.+.}-{4:4}, at: inet6_rtm_deladdr+0x23d/0x370 net/ipv6/addrconf.c:4811 2 locks held by getty/5372: #0: ffff8880353a60a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000322b2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13a0 drivers/tty/n_tty.c:2211 3 locks held by kworker/1:3/5735: #0: ffff88813fe43140 ( (wq_completion)events ){+.+.}-{0:0} , at: process_one_work kernel/workqueue.c:3277 [inline] , at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3385 #1: ffffc900041f7c40 (rx_mode_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3278 [inline] ffffc900041f7c40 (rx_mode_work){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3385 #2: ffffffff8fdce8c0 (rtnl_mutex){+.+.}-{4:4}, at: netdev_rx_mode_work+0x19/0x3c0 net/core/dev_addr_lists.c:1312 3 locks held by kworker/1:6/5765: #0: ffff88813fe43140 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3277 [inline] #0: ffff88813fe43140 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3385 #1: ffffc9000246fc40 ( deferred_process_work ){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3278 [inline] ){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3385 #2: ffffffff8fdce8c0 (rtnl_mutex){+.+.}-{4:4}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104 5 locks held by kworker/u8:16/5986: #0: ffff88801be86140 ( (wq_completion)netns ){+.+.}-{0:0} , at: process_one_work kernel/workqueue.c:3277 [inline] , at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3385 #1: ffffc9000535fc40 ( net_cleanup_work ){+.+.}-{0:0} , at: process_one_work kernel/workqueue.c:3278 [inline] , at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3385 #2: ffffffff8fdbfc08 ( pernet_ops_rwsem ){++++}-{4:4} , at: cleanup_net+0xf4/0x800 net/core/net_namespace.c:673 #3: ffffffff8fdce8c0 (rtnl_mutex){+.+.}-{4:4}, at: ops_exit_rtnl_list net/core/net_namespace.c:173 [inline] (rtnl_mutex){+.+.}-{4:4}, at: ops_undo_list+0x2a4/0x940 net/core/net_namespace.c:248 #4: ffffffff8e963068 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline] (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2d0/0x770 kernel/rcu/tree_exp.h:961 3 locks held by kworker/u8:24/6001: #0: ffff88813fe7c140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3277 [inline] #0: ffff88813fe7c140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3385 #1: ffffc9000546fc40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3278 [inline] #1: ffffc9000546fc40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3385 #2: ffffffff8fdce8c0 ( rtnl_mutex ){+.+.}-{4:4} , at: linkwatch_event+0xe/0x60 net/core/link_watch.c:313 8 locks held by syz.7.250/7292: 1 lock held by segctord/7286: #0: ffff88802c331288 (&nilfs->ns_segctor_sem){++++}-{4:4}, at: nilfs_transaction_lock+0x252/0x4c0 fs/nilfs2/segment.c:357 2 locks held by syz-executor/8443: #0: ffffffff8f54c3c8 ( &ops->srcu #2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570 #1: ffffffff8fdce8c0 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x883/0x1bb0 net/core/rtnetlink.c:4108 1 lock held by syz-executor/8446: #0: ffffffff8fdce8c0 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #0: ffffffff8fdce8c0 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #0: ffffffff8fdce8c0 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x883/0x1bb0 net/core/rtnetlink.c:4108 1 lock held by syz-executor/8461: #0: ffffffff8fdce8c0 ( rtnl_mutex ){+.+.}-{4:4} , at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] , at: inet6_rtm_newaddr+0x65f/0xe30 net/ipv6/addrconf.c:5039 1 lock held by syz-executor/8465: #0: ffffffff8fdce8c0 (rtnl_mutex){+.+.}-{4:4} , at: rtnl_lock net/core/rtnetlink.c:80 [inline] , at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] , at: rtnl_newlink+0x883/0x1bb0 net/core/rtnetlink.c:4108 1 lock held by syz.0.397/8574: #0: ffffffff8fdce8c0 ( rtnl_mutex ){+.+.}-{4:4} , at: __tun_chr_ioctl+0x3bc/0x1e10 drivers/net/tun.c:3080 1 lock held by syz.0.397/8575: #0: ffffffff8fdce8c0 ( rtnl_mutex ){+.+.}-{4:4} , at: __tun_chr_ioctl+0x3bc/0x1e10 drivers/net/tun.c:3080 1 lock held by syz.0.397/8577: #0: ffffffff8fdce8c0 ( rtnl_mutex ){+.+.}-{4:4} , at: __tun_chr_ioctl+0x3bc/0x1e10 drivers/net/tun.c:3080 1 lock held by syz.0.397/8579: #0: ffffffff8fdce8c0 ( rtnl_mutex ){+.+.}-{4:4} , at: rtnl_lock net/core/rtnetlink.c:80 [inline] , at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] , at: rtnl_newlink+0x883/0x1bb0 net/core/rtnetlink.c:4108 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP 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 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 7292 Comm: syz.7.250 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 RIP: 0010:rdtsc_ordered arch/x86/include/asm/tsc.h:57 [inline] RIP: 0010:delay_tsc+0x71/0xc0 arch/x86/lib/delay.c:72 Code: 00 00 e8 c2 6f ed f5 65 8b 05 4b 59 92 07 85 c0 74 1c f3 90 bf 01 00 00 00 e8 0b 6e ed f5 e8 46 79 01 00 39 c5 75 0e 0f 01 f9 <66> 90 eb bd e8 26 44 8d f5 eb dd 4c 29 fb e8 2c 79 01 00 89 c5 0f RSP: 0018:ffffc90004476a30 EFLAGS: 00000046 RAX: 000000003cb66564 RBX: 0000000000000993 RCX: 0000000000000000 RDX: 00000000000000d0 RSI: ffffffff8c28aa40 RDI: ffffffff8c28aa00 RBP: 0000000000000000 R08: ffff8880259d8237 R09: 1ffff11004b3b046 R10: dffffc0000000000 R11: ffffffff8ba65690 R12: 1ffffffff34f3542 R13: 00000000ffffffff R14: 000000d03cb6640d R15: 00000000000000dd FS: 00007fa6b4dbc6c0(0000) GS:ffff888125295000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000564317863138 CR3: 00000000330f7000 CR4: 0000000000350ef0 Call Trace: udelay include/asm-generic/delay.h:62 [inline] wait_for_lsr+0x160/0x2f0 drivers/tty/serial/8250/8250_port.c:1976 serial8250_fifo_wait_for_lsr_thre drivers/tty/serial/8250/8250_port.c:3207 [inline] serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3272 [inline] serial8250_console_write+0x1348/0x1ba0 drivers/tty/serial/8250/8250_port.c:3357 console_emit_next_record kernel/printk/printk.c:3183 [inline] console_flush_one_record kernel/printk/printk.c:3269 [inline] console_flush_all+0x718/0xb20 kernel/printk/printk.c:3343 __console_flush_and_unlock kernel/printk/printk.c:3373 [inline] console_unlock+0xd1/0x1c0 kernel/printk/printk.c:3413 vprintk_emit+0x485/0x560 kernel/printk/printk.c:2479 _printk+0xdd/0x130 kernel/printk/printk.c:2504 __nilfs_msg+0x373/0x450 fs/nilfs2/super.c:78 nilfs_sufile_updatev+0x21c/0x6d0 fs/nilfs2/sufile.c:186 nilfs_sufile_freev fs/nilfs2/sufile.h:93 [inline] nilfs_free_segments fs/nilfs2/segment.c:1140 [inline] nilfs_segctor_collect_blocks fs/nilfs2/segment.c:1261 [inline] nilfs_segctor_collect fs/nilfs2/segment.c:1547 [inline] nilfs_segctor_do_construct+0x1f55/0x76c0 fs/nilfs2/segment.c:2122 nilfs_segctor_construct+0x17b/0x690 fs/nilfs2/segment.c:2462 nilfs_clean_segments+0x3bd/0xa50 fs/nilfs2/segment.c:2536 nilfs_ioctl_clean_segments fs/nilfs2/ioctl.c:922 [inline] nilfs_ioctl+0x261f/0x2780 fs/nilfs2/ioctl.c:1352 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583 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: 0033:0x7fa6b3f9cdd9 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:00007fa6b4dbc028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fa6b4216090 RCX: 00007fa6b3f9cdd9 RDX: 0000200000000640 RSI: 0000000040786e88 RDI: 0000000000000006 RBP: 00007fa6b4032d69 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fa6b4216128 R14: 00007fa6b4216090 R15: 00007ffe72b31b38