INFO: task syz-executor:11038 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:22384 pid:11038 ppid:1 flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5245 [inline]
__schedule+0x107f/0x4030 kernel/sched/core.c:6562
schedule+0xb9/0x180 kernel/sched/core.c:6638
wb_wait_for_completion+0x16f/0x290 fs/fs-writeback.c:191
sync_inodes_sb+0x1c5/0xa10 fs/fs-writeback.c:2756
sync_filesystem+0x16d/0x220 fs/sync.c:64
generic_shutdown_super+0x6b/0x340 fs/super.c:474
kill_block_super+0x7c/0xe0 fs/super.c:1470
deactivate_locked_super+0x93/0xf0 fs/super.c:332
cleanup_mnt+0x471/0x4f0 fs/namespace.c:1191
task_work_run+0x1d0/0x260 kernel/task_work.c:203
exit_task_work include/linux/task_work.h:39 [inline]
do_exit+0x9d5/0x2570 kernel/exit.c:881
do_group_exit+0x229/0x2e0 kernel/exit.c:1024
__do_sys_exit_group kernel/exit.c:1035 [inline]
__se_sys_exit_group kernel/exit.c:1033 [inline]
__x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1033
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fc723b9de99
RSP: 002b:00007ffc41a5c778 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007fc723c3336a RCX: 00007fc723b9de99
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000001
RBP: 000000000000000c R08: 0000000000000000 R09: 00007fc723c3330a
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffc41a5da30
R13: 00007fc723c3330a R14: 000055557e4c64e8 R15: 00007ffc41a5eb00
Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
#0: ffffffff8cb2e4f0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xef0 kernel/rcu/tasks.h:517
1 lock held by rcu_tasks_trace/13:
#0: ffffffff8cb2ed10 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xef0 kernel/rcu/tasks.h:517
3 locks held by kworker/1:0/22:
1 lock held by khungtaskd/27:
#0: ffffffff8cb2db60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
#0: ffffffff8cb2db60 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
#0: ffffffff8cb2db60 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6527
4 locks held by kworker/u4:3/46:
#0: ffff888017479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267
#1: ffffc90000b77d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267
#2: ffffffff8dd58c28 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xa/0x50 net/core/link_watch.c:263
#3: ffffffff8cb33838 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:291 [inline]
#3: ffffffff8cb33838 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x2ec/0x890 kernel/rcu/tree_exp.h:962
2 locks held by getty/4027:
#0: ffff888030512098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244
#1: ffffc9000327b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x41e/0x1360 drivers/tty/n_tty.c:2198
2 locks held by kworker/u4:7/4350:
#0: ffff88814465d138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267
#1: ffffc90004437d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267
2 locks held by kworker/u4:15/6202:
#0: ffff88814465d138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267
#1: ffffc90003f27d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267
3 locks held by kworker/u4:17/6207:
2 locks held by syz-executor/11038:
#0: ffff88806558a0e0 (&type->s_umount_key#65){+.+.}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:362
#1: ffff888024a647d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:362 [inline]
#1: ffff888024a647d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x1a9/0xa10 fs/fs-writeback.c:2754
6 locks held by segctord/12068:
2 locks held by syz-executor/12792:
#0: ffff888068d900e0 (&type->s_umount_key#65){+.+.}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:362
#1: ffff8881423947d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:362 [inline]
#1: ffff8881423947d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x1a9/0xa10 fs/fs-writeback.c:2754
1 lock held by segctord/13387:
1 lock held by rm/14689:
=============================================
NMI backtrace for cpu 1
CPU: 1 PID: 27 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/25/2026
Call Trace:
dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106
nmi_cpu_backtrace+0x3e6/0x460 lib/nmi_backtrace.c:111
nmi_trigger_cpumask_backtrace+0x1d4/0x450 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline]
watchdog+0xf0e/0xf50 kernel/hung_task.c:377
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 13387 Comm: segctord Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/25/2026
RIP: 0010:check_kcov_mode kernel/kcov.c:184 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:245 [inline]
RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x2c/0x80 kernel/kcov.c:313
Code: 04 24 65 48 8b 15 34 4a 80 7e 65 8b 0d 35 4a 80 7e 81 e1 00 01 ff 00 74 11 81 f9 00 01 00 00 75 5b 83 ba 1c 16 00 00 00 74 52 <8b> 8a f8 15 00 00 83 f9 03 75 47 48 8b 8a 00 16 00 00 44 8b 8a fc
RSP: 0018:ffffc90004ca70f8 EFLAGS: 00000246
RAX: ffffffff81abe997 RBX: 0000000000000001 RCX: 0000000000000000
RDX: ffff88804977bc00 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90004ca7220 R08: ffffea00009ee5b7 R09: 1ffffd400013dcb6
R10: dffffc0000000000 R11: fffff9400013dcb7 R12: 1ffff92000994e28
R13: dffffc0000000000 R14: ffffea00009ee580 R15: 0000000000000007
FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f63f8bbde9c CR3: 0000000077472000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
rcu_read_unlock include/linux/rcupdate.h:820 [inline]
mapping_get_entry mm/filemap.c:1899 [inline]
__filemap_get_folio+0x337/0xde0 mm/filemap.c:1943
pagecache_get_page+0x26/0x260 mm/folio-compat.c:110
find_or_create_page include/linux/pagemap.h:648 [inline]
grab_cache_page include/linux/pagemap.h:780 [inline]
nilfs_grab_buffer+0xb1/0x590 fs/nilfs2/page.c:56
nilfs_mdt_submit_block+0xb1/0x780 fs/nilfs2/mdt.c:120
nilfs_mdt_read_block+0x47/0x320 fs/nilfs2/mdt.c:175
nilfs_mdt_get_block+0x14f/0xac0 fs/nilfs2/mdt.c:250
nilfs_sufile_get_segment_usage_block fs/nilfs2/sufile.c:92 [inline]
nilfs_sufile_set_segment_usage+0x143/0x570 fs/nilfs2/sufile.c:556
nilfs_cancel_segusage fs/nilfs2/segment.c:1491 [inline]
nilfs_segctor_abort_construction+0x740/0xde0 fs/nilfs2/segment.c:1841
nilfs_segctor_do_construct+0x60ee/0x6980 fs/nilfs2/segment.c:2153
nilfs_segctor_construct+0x170/0x690 fs/nilfs2/segment.c:2453
nilfs_segctor_thread_construct fs/nilfs2/segment.c:2561 [inline]
nilfs_segctor_thread+0x527/0x1050 fs/nilfs2/segment.c:2645
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295