INFO: task hung in nilfs_segctor_thread (8)

Status: auto-obsoleted due to no activity on 2026/10/30 04:44
Subsystems: nilfs
Labels: prio:high
[Documentation on labels]
First crash: 61d, last: 61d
▶ ▼ ✨ AI Jobs (1)
ID Workflow Result Correct Bug Created Started Finished Revision
da4b82ce assessment-security DenialOfService: ✅ Exploitable: ❌ FilesystemTrigger: ✅ NetworkTrigger: ❌ PeripheralTrigger: ✅ RemoteTrigger: ❌ Unprivileged: ❌ UserNamespace: ❌ VMGuestTrigger: ❌ VMHostTrigger: ❌ ❓ INFO: task hung in nilfs_segctor_thread (8) 2026/09/02 00:00 2026/09/02 00:00 2026/09/02 00:29 587f6b29
▶ ▼ Similar bugs (16)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in nilfs_segctor_thread (5) nilfs 1 1 489d 489d 0/29 auto-obsoleted due to no activity on 2025/09/27 08:54
linux-6.6 INFO: task hung in nilfs_segctor_thread 1 1 124d 124d 0/2 auto-obsoleted due to no activity on 2026/10/06 21:10
linux-4.19 INFO: task hung in nilfs_segctor_thread nilfs2 1 syz, C 41 1355d 1456d 0/1 upstream: reported C repro on 2022/11/05 03:06
linux-5.15 INFO: task hung in nilfs_segctor_thread (4) origin:upstream 1 syz, C error 9 66d 215d 0/3 upstream: reported C repro on 2026/03/30 01:14
upstream INFO: task hung in nilfs_segctor_thread (6) nilfs 1 syz, C done 41 178d 318d 29/29 fixed on 2026/05/06 16:40
linux-5.15 INFO: task hung in nilfs_segctor_thread (2) 1 2 822d 902d 0/3 auto-obsoleted due to no activity on 2024/11/07 22:53
upstream INFO: task hung in nilfs_segctor_thread (3) nilfs 1 138 809d 834d 0/29 auto-obsoleted due to no activity on 2024/10/22 18:08
upstream INFO: task hung in nilfs_segctor_thread nilfs 1 syz, C error 94 1277d 1451d 22/29 fixed on 2023/06/08 14:41
linux-5.15 INFO: task hung in nilfs_segctor_thread 1 3 1288d 1300d 0/3 auto-obsoleted due to no activity on 2023/08/20 05:29
upstream INFO: task hung in nilfs_segctor_thread (7) prio:high nilfs 1 syz error 18 137d 136d 0/29 closed as dup on 2026/06/19 02:51
upstream INFO: task hung in nilfs_segctor_thread (4) nilfs 1 1 728d 728d 0/29 auto-obsoleted due to no activity on 2025/01/31 15:40
linux-4.14 INFO: task hung in nilfs_segctor_thread nilfs2 1 syz, C 1 1353d 1353d 0/1 upstream: reported C repro on 2023/02/16 07:03
linux-6.1 INFO: task hung in nilfs_segctor_thread (2) 1 2 215d 298d 0/3 auto-obsoleted due to no activity on 2026/07/07 21:46
upstream INFO: task hung in nilfs_segctor_thread (2) nilfs 1 syz, C inconclusive 98 875d 985d 26/29 fixed on 2024/07/09 19:14
linux-6.1 INFO: task hung in nilfs_segctor_thread 1 40 758d 902d 0/3 auto-obsoleted due to no activity on 2024/12/12 18:46
linux-5.15 INFO: task hung in nilfs_segctor_thread (3) 1 1 697d 697d 0/3 auto-obsoleted due to no activity on 2025/03/13 18:17

Sample crash report:
INFO: task segctord:18941 blocked for more than 143 seconds.
      Tainted: G             L      syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:segctord        state:D stack:25496 pid:18941 tgid:18941 ppid:2      task_flags:0x200040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5520 [inline]
 __schedule+0x17db/0x58f0 kernel/sched/core.c:7270
 __schedule_loop kernel/sched/core.c:7347 [inline]
 schedule+0x164/0x2b0 kernel/sched/core.c:7362
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7419
 rwsem_down_write_slowpath+0x87d/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:1632
 nilfs_transaction_lock+0x24a/0x4b0 fs/nilfs2/segment.c:357
 nilfs_segctor_thread_construct fs/nilfs2/segment.c:2599 [inline]
 nilfs_segctor_thread+0x6be/0xdb0 fs/nilfs2/segment.c:2714
 kthread+0x38b/0x480 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
 </TASK>

Showing all locks held in the system:
locks held by pool_workqueue_/3: 1, on CPU#1:
 #0: ffffffff8ed62ae8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline]
 #0: ffffffff8ed62ae8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2d0/0x770 kernel/rcu/tree_exp.h:966
locks held by khungtaskd/32: 1, last CPU#0:
 #0: ffffffff8ed5c720 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
 #0: ffffffff8ed5c720 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #0: ffffffff8ed5c720 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6837
locks held by jfsCommit/119: 2, last CPU#1:
 #0: ffff8880552b1bb8 (&jfs_ip->rdwrlock#2/2){++++}-{4:4}, at: dbFree+0xe4/0x650 fs/jfs/jfs_dmap.c:441
 #1: ffffffff8ec36338 (console_srcu){....}-{0:0}, at: rcu_try_lock_acquire include/linux/rcupdate.h:314 [inline]
 #1: ffffffff8ec36338 (console_srcu){....}-{0:0}, at: srcu_read_lock_nmisafe include/linux/srcu.h:439 [inline]
 #1: ffffffff8ec36338 (console_srcu){....}-{0:0}, at: console_srcu_read_lock+0x30/0x60 kernel/printk/printk.c:291
locks held by klogd/4974: 1, last CPU#0:
 #0: ffffffff8ed4e980 (syslog_lock){+.+.}-{4:4}, at: syslog_print+0x2ce/0x610 kernel/printk/printk.c:1613
locks held by dhcpcd/5280: 1, on CPU#0:
 #0: ffffffff90251a80 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:134 [inline]
 #0: ffffffff90251a80 (rtnl_mutex){+.+.}-{4:4}, at: inet6_rtm_deladdr+0x249/0x390 net/ipv6/addrconf.c:4835
locks held by getty/5373: 2, on CPU#1:
 #0: ffff8880355fe0a0 (&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+0x45a/0x1360 drivers/tty/n_tty.c:2211
locks held by kworker/1:3/5714: 3, last CPU#1:
 #0: ffff88801b06b140 ((wq_completion)events){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
 #0: ffff88801b06b140 ((wq_completion)events){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #0: ffff88801b06b140 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline]
 #0: ffff88801b06b140 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479
 #1: ffffc900047c7c40 (drain_vmap_work){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
 #1: ffffc900047c7c40 (drain_vmap_work){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #1: ffffc900047c7c40 (drain_vmap_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline]
 #1: ffffc900047c7c40 (drain_vmap_work){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479
 #2: ffffffff8ee8b7c0 (vmap_purge_lock){+.+.}-{4:4}, at: drain_vmap_area_work+0x17/0x40 mm/vmalloc.c:2451
locks held by kworker/0:9/9024: 3, on CPU#0:
 #0: ffff88801b06b140 ((wq_completion)events){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
 #0: ffff88801b06b140 ((wq_completion)events){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #0: ffff88801b06b140 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline]
 #0: ffff88801b06b140 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479
 #1: ffffc90003a57c40 (deferred_process_work){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
 #1: ffffc90003a57c40 (deferred_process_work){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #1: ffffc90003a57c40 (deferred_process_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline]
 #1: ffffc90003a57c40 (deferred_process_work){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479
 #2: ffffffff90251a80 (rtnl_mutex){+.+.}-{4:4}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104
locks held by kworker/u8:17/9059: 3, on CPU#0:
 #0: ffff88801c2d6140 ((wq_completion)netns){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
 #0: ffff88801c2d6140 ((wq_completion)netns){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #0: ffff88801c2d6140 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline]
 #0: ffff88801c2d6140 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479
 #1: ffffc9000e05fc40 (net_cleanup_work){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
 #1: ffffc9000e05fc40 (net_cleanup_work){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #1: ffffc9000e05fc40 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline]
 #1: ffffc9000e05fc40 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479
 #2: ffffffff90243208 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf5/0x810 net/core/net_namespace.c:677
locks held by kworker/u8:19/10612: 3, on CPU#0:
 #0: ffff888031f35940 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
 #0: ffff888031f35940 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #0: ffff888031f35940 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline]
 #0: ffff888031f35940 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479
 #1: ffffc9000204fc40 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
 #1: ffffc9000204fc40 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #1: ffffc9000204fc40 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline]
 #1: ffffc9000204fc40 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479
 #2: ffffffff90251a80 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:134 [inline]
 #2: ffffffff90251a80 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_verify_work+0x19/0x30 net/ipv6/addrconf.c:4770
locks held by kworker/u8:20/12763: 3, on CPU#0:
 #0: ffff88801b0ac140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
 #0: ffff88801b0ac140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #0: ffff88801b0ac140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline]
 #0: ffff88801b0ac140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479
 #1: ffffc9000545fc40 ((linkwatch_work).work){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
 #1: ffffc9000545fc40 ((linkwatch_work).work){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #1: ffffc9000545fc40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline]
 #1: ffffc9000545fc40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479
 #2: ffffffff90251a80 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:313
locks held by syz-executor/12782: 2, on CPU#0:
 #0: ffff888031fc00e8 (&type->s_umount_key#73){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline]
 #0: ffff888031fc00e8 (&type->s_umount_key#73){++++}-{4:4}, at: __super_lock_excl fs/super.c:75 [inline]
 #0: ffff888031fc00e8 (&type->s_umount_key#73){++++}-{4:4}, at: deactivate_super+0xac/0xe0 fs/super.c:631
 #1: ffffffff8f213c40 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xad/0x530 fs/jfs/jfs_logmgr.c:1441
locks held by dhcpcd/15678: 1, on CPU#0:
 #0: ffff8880552ad880 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1024 [inline]
 #0: ffff8880552ad880 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: __sock_release+0x7a/0x1f0 net/socket.c:734
locks held by syz.7.2469/18950: 3, last CPU#0:
 #0: ffff888034246460 (sb_writers#28){.+.+}-{0:0}, at: mnt_want_write_file+0x60/0x200 fs/namespace.c:538
 #1: ffff8880afe48288 (&nilfs->ns_segctor_sem){++++}-{4:4}, at: nilfs_transaction_lock+0x24a/0x4b0 fs/nilfs2/segment.c:357
 #2: ffffffff8ec36338 (console_srcu){....}-{0:0}, at: rcu_try_lock_acquire include/linux/rcupdate.h:314 [inline]
 #2: ffffffff8ec36338 (console_srcu){....}-{0:0}, at: srcu_read_lock_nmisafe include/linux/srcu.h:439 [inline]
 #2: ffffffff8ec36338 (console_srcu){....}-{0:0}, at: console_srcu_read_lock+0x30/0x60 kernel/printk/printk.c:291
locks held by segctord/18941: 1, on CPU#1:
 #0: ffff8880afe48288 (&nilfs->ns_segctor_sem){++++}-{4:4}, at: nilfs_transaction_lock+0x24a/0x4b0 fs/nilfs2/segment.c:357
locks held by syz-executor/19055: 2, on CPU#0:
 #0: ffff888085558ea0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:500 [inline]
 #0: ffff888085558ea0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x22a/0x5b0 net/bluetooth/hci_core.c:2681
 #1: ffffffff8ed62ae8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline]
 #1: ffffffff8ed62ae8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770 kernel/rcu/tree_exp.h:966
locks held by syz-executor/19317: 2, on CPU#0:
 #0: ffffffff8fa90e28 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
 #0: ffffffff8fa90e28 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #0: ffffffff8fa90e28 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:595
 #1: ffffffff90251a80 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
 #1: ffffffff90251a80 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:366 [inline]
 #1: ffffffff90251a80 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0xc10/0x1c30 net/core/rtnetlink.c:4214
locks held by syz-executor/19424: 1, on CPU#0:
 #0: ffffffff90251a80 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
 #0: ffffffff90251a80 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:366 [inline]
 #0: ffffffff90251a80 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0xc10/0x1c30 net/core/rtnetlink.c:4214
locks held by syz.3.2562/19437: 1, on CPU#0:
 #0: ffffffff90243208 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x524/0x780 net/core/net_namespace.c:578
locks held by syz-executor/19504: 1, on CPU#0:
 #0: ffffffff90251a80 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:134 [inline]
 #0: ffffffff90251a80 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x470/0x19f0 net/ipv4/devinet.c:978
locks held by syz-executor/19507: 1, on CPU#0:
 #0: ffffffff90251a80 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:134 [inline]
 #0: ffffffff90251a80 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x470/0x19f0 net/ipv4/devinet.c:978
locks held by syz-executor/19517: 1, on CPU#0:
 #0: ffffffff90251a80 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:134 [inline]
 #0: ffffffff90251a80 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x470/0x19f0 net/ipv4/devinet.c:978
locks held by syz-executor/19523: 1, on CPU#0:
 #0: ffffffff90251a80 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:134 [inline]
 #0: ffffffff90251a80 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x470/0x19f0 net/ipv4/devinet.c:978
locks held by syz-executor/19531: 1, on CPU#0:
 #0: ffffffff90251a80 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:134 [inline]
 #0: ffffffff90251a80 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x470/0x19f0 net/ipv4/devinet.c:978

=============================================

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 32 Comm: khungtaskd Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
 <TASK>
 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/0x480 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
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 119 Comm: jfsCommit Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:io_serial_in+0x77/0xc0 drivers/tty/serial/8250/8250_port.c:409
Code: e8 0e 27 55 fc 44 89 f9 d3 e3 49 83 c6 40 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 3f 23 c5 fc 41 03 1e 89 da ec <0f> b6 c0 5b 41 5c 41 5e 41 5f c3 cc cc cc cc cc 44 89 f9 80 e1 07
RSP: 0018:ffffc90002d76f98 EFLAGS: 00000002
RAX: 1ffffffff35a6a00 RBX: 00000000000003fd RCX: 0000000000000000
RDX: 00000000000003fd RSI: 0000000000000000 RDI: 0000000000000020
RBP: dffffc0000000000 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: ffffffff85729970 R12: dffffc0000000000
R13: 0000000000000000 R14: ffffffff9ad35100 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff888124dd6000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffd1d8ec288 CR3: 000000007f0d6000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 serial_in drivers/tty/serial/8250/8250.h:128 [inline]
 serial_lsr_in drivers/tty/serial/8250/8250.h:150 [inline]
 wait_for_lsr+0x184/0x2f0 drivers/tty/serial/8250/8250_port.c:2013
 serial8250_fifo_wait_for_lsr_thre drivers/tty/serial/8250/8250_port.c:3270 [inline]
 __serial8250_console_fifo_write+0xcd/0x3e0 drivers/tty/serial/8250/8250_port.c:3345
 serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3378 [inline]
 __serial8250_console_write drivers/tty/serial/8250/8250_port.c:3429 [inline]
 serial8250_console_write+0xaa1/0x1200 drivers/tty/serial/8250/8250_port.c:3493
 nbcon_emit_next_record+0xef5/0x1a90 kernel/printk/nbcon.c:-1
 __nbcon_atomic_flush_pending_con+0x1d2/0x370 kernel/printk/nbcon.c:1592
 nbcon_atomic_flush_pending_con kernel/printk/nbcon.c:1626 [inline]
 __nbcon_atomic_flush_pending+0x37f/0x440 kernel/printk/nbcon.c:1675
 vprintk_emit+0x1a6/0x560 kernel/printk/printk.c:2458
 _printk+0xdd/0x130 kernel/printk/printk.c:2504
 __warn+0xff/0x4c0 kernel/panic.c:1082
 __report_bug+0x276/0x570 lib/bug.c:254
 report_bug+0x16b/0x220 lib/bug.c:286
 handle_bug+0x9c/0x200 arch/x86/kernel/traps.c:436
 exc_invalid_op+0x1a/0x50 arch/x86/kernel/traps.c:490
 asm_exc_invalid_op+0x1a/0x20 arch/x86/include/asm/idtentry.h:593
RIP: 0010:dbAdjTree fs/jfs/jfs_dmap.c:2962 [inline]
RIP: 0010:dbJoin+0xc33/0xd60 fs/jfs/jfs_dmap.c:2930
Code: eb 0c e8 50 e9 58 fe eb 05 e8 49 e9 58 fe 31 c0 48 83 c4 68 5b 41 5c 41 5d 41 5e 41 5f 5d e9 04 d1 78 08 cc e8 2e e9 58 fe 90 <0f> 0b 90 eb df 44 89 e9 80 e1 07 38 c1 0f 8c 00 f4 ff ff 4c 89 ef
RSP: 0018:ffffc90002d77a28 EFLAGS: 00010293
RAX: ffffffff836ed7a2 RBX: 0000000000000155 RCX: ffff88801ef2be80
RDX: 0000000000000000 RSI: 0000000000000155 RDI: 0000000000020056
RBP: 0000000000000004 R08: ffffea000095b4c7 R09: 1ffffd400012b698
R10: dffffc0000000000 R11: fffff9400012b699 R12: dffffc0000000000
R13: ffff8880256d3020 R14: 0000000000020056 R15: 0000000000000004
 dbFreeBits+0x4a2/0xd70 fs/jfs/jfs_dmap.c:2427
 dbFreeDmap fs/jfs/jfs_dmap.c:2176 [inline]
 dbFree+0x324/0x650 fs/jfs/jfs_dmap.c:485
 txFreeMap+0x7ff/0xde0 fs/jfs/jfs_txnmgr.c:2536
 txUpdateMap+0x32d/0x9f0 fs/jfs/jfs_txnmgr.c:-1
 txLazyCommit fs/jfs/jfs_txnmgr.c:2666 [inline]
 jfs_lazycommit+0x44c/0xac0 fs/jfs/jfs_txnmgr.c:2735
 kthread+0x38b/0x480 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
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/08/31 04:33 linux-next e30626823a40 2f52988a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: task hung in nilfs_segctor_thread
* Struck through repros no longer work on HEAD.