INFO: task syz.0.1393:19523 blocked for more than 143 seconds.
Not tainted 6.16.0-rc5-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.1393 state:D stack:26088 pid:19523 tgid:19517 ppid:17750 task_flags:0x400040 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5401 [inline]
__schedule+0x16a2/0x4cb0 kernel/sched/core.c:6790
__schedule_loop kernel/sched/core.c:6868 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6883
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6940
rwsem_down_write_slowpath+0xbec/0x1030 kernel/locking/rwsem.c:1176
__down_write_common kernel/locking/rwsem.c:1304 [inline]
__down_write kernel/locking/rwsem.c:1313 [inline]
down_write+0x1ab/0x1f0 kernel/locking/rwsem.c:1578
f2fs_down_write fs/f2fs/f2fs.h:2229 [inline]
f2fs_balance_fs+0x558/0x750 fs/f2fs/segment.c:463
f2fs_symlink+0x6c3/0x880 fs/f2fs/namei.c:693
vfs_symlink+0x140/0x2f0 fs/namei.c:4739
do_symlinkat+0x1b1/0x3f0 fs/namei.c:4765
__do_sys_symlink fs/namei.c:4786 [inline]
__se_sys_symlink fs/namei.c:4784 [inline]
__x64_sys_symlink+0x7a/0x90 fs/namei.c:4784
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fcab4f8e929
RSP: 002b:00007fcab5dec038 EFLAGS: 00000246 ORIG_RAX: 0000000000000058
RAX: ffffffffffffffda RBX: 00007fcab51b6160 RCX: 00007fcab4f8e929
RDX: 0000000000000000 RSI: 0000200000000cc0 RDI: 000020000000a900
RBP: 00007fcab5010b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000001 R14: 00007fcab51b6160 R15: 00007ffdb5b50c18
Showing all locks held in the system:
5 locks held by kworker/u8:0/12:
#0: ffff88801b2fb948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88801b2fb948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321
#1: ffffc90000117bc0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc90000117bc0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321
#2: ffffffff8f4fdfd0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x800 net/core/net_namespace.c:662
#3: ffffffff8f50abc8 (rtnl_mutex){+.+.}-{4:4}, at: ops_exit_rtnl_list net/core/net_namespace.c:174 [inline]
#3: ffffffff8f50abc8 (rtnl_mutex){+.+.}-{4:4}, at: ops_undo_list+0x2a4/0x990 net/core/net_namespace.c:249
#4: ffffffff8e144978 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:304 [inline]
#4: ffffffff8e144978 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730 kernel/rcu/tree_exp.h:998
1 lock held by khungtaskd/31:
#0: ffffffff8e13ee60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e13ee60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e13ee60 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770
3 locks held by kworker/u8:3/49:
#0: ffff88801a489148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88801a489148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321
#1: ffffc90000b97bc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc90000b97bc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321
#2: ffffffff8f50abc8 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:303
3 locks held by kworker/u8:5/147:
#0: ffff88814c3c5948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88814c3c5948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321
#1: ffffc90002ed7bc0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc90002ed7bc0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321
#2: ffffffff8f50abc8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#2: ffffffff8f50abc8 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x112/0x14b0 net/ipv6/addrconf.c:4198
4 locks held by kworker/u8:6/1113:
#0: ffff88801e6db148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88801e6db148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321
#1: ffffc90003c9fbc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc90003c9fbc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321
#2: ffff88804efd60e0 (&type->s_umount_key#85){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:563
#3: ffff888035479410 (&sbi->gc_lock){+.+.}-{4:4}, at: f2fs_down_write fs/f2fs/f2fs.h:2229 [inline]
#3: ffff888035479410 (&sbi->gc_lock){+.+.}-{4:4}, at: f2fs_balance_fs+0x558/0x750 fs/f2fs/segment.c:463
2 locks held by kworker/u8:7/1161:
#0: ffff88801c797148 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88801c797148 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321
#1: ffffc90003e0fbc0 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc90003e0fbc0 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321
3 locks held by kworker/0:2/1210:
#0: ffff88801a480d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88801a480d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321
#1: ffffc90003fcfbc0 (deferred_process_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc90003fcfbc0 (deferred_process_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321
#2: ffffffff8f50abc8 (rtnl_mutex){+.+.}-{4:4}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104
2 locks held by dhcpcd/5499:
#0: ffffffff8f4ef4e8 (vlan_ioctl_mutex){+.+.}-{4:4}, at: sock_ioctl+0x5ee/0x790 net/socket.c:1273
#1: ffffffff8f50abc8 (rtnl_mutex){+.+.}-{4:4}, at: vlan_ioctl_handler+0xd0/0x650 net/8021q/vlan.c:553
2 locks held by getty/5596:
#0: ffff888030f2d0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000333b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
7 locks held by syz.0.1393/19518:
3 locks held by syz.0.1393/19523:
#0: ffff88804efd6428 (sb_writers#25){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:557
#1: ffff88805a20a508 (&type->i_mutex_dir_key#16/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:914 [inline]
#1: ffff88805a20a508 (&type->i_mutex_dir_key#16/1){+.+.}-{4:4}, at: filename_create+0x1f9/0x470 fs/namei.c:4148
#2: ffff888035479410 (&sbi->gc_lock){+.+.}-{4:4}, at: f2fs_down_write fs/f2fs/f2fs.h:2229 [inline]
#2: ffff888035479410 (&sbi->gc_lock){+.+.}-{4:4}, at: f2fs_balance_fs+0x558/0x750 fs/f2fs/segment.c:463
1 lock held by syz-executor/21352:
#0: ffffffff8f50abc8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#0: ffffffff8f50abc8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#0: ffffffff8f50abc8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8db/0x1c70 net/core/rtnetlink.c:4054
1 lock held by syz-executor/21478:
#0: ffffffff8f50abc8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#0: ffffffff8f50abc8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#0: ffffffff8f50abc8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8db/0x1c70 net/core/rtnetlink.c:4054
1 lock held by syz-executor/21618:
#0: ffffffff8f50abc8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#0: ffffffff8f50abc8 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x3b0/0x18b0 net/ipv4/devinet.c:979
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc5-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:307 [inline]
watchdog+0xfee/0x1030 kernel/hung_task.c:470
kthread+0x711/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
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: 36 Comm: kworker/u8:2 Not tainted 6.16.0-rc5-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: 0x0 (events_unbound)
RIP: 0010:update_sd_lb_stats kernel/sched/fair.c:11042 [inline]
RIP: 0010:sched_balance_find_src_group kernel/sched/fair.c:11321 [inline]
RIP: 0010:sched_balance_rq+0x792/0x57a0 kernel/sched/fair.c:11783
Code: 80 02 00 00 31 f6 e8 0d 05 8b 00 c7 84 24 e0 02 00 00 ff ff ff ff ba 7c 00 00 00 48 8b bc 24 48 01 00 00 31 f6 e8 ee 04 8b 00 <48> 8b 9c 24 c0 03 00 00 48 83 c3 10 48 89 d8 48 c1 e8 03 42 80 3c
RSP: 0018:ffffc90000ac73c0 EFLAGS: 00000046
RAX: ffffc90000ac76a4 RBX: ffff8880b8739e88 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffc90000ac7720
RBP: ffffc90000ac7868 R08: 0000000000000004 R09: 0000000000000004
R10: ffffc90000ac76a4 R11: fffff52000158ee4 R12: ffff8880b8723e48
R13: dffffc0000000000 R14: ffff8880b8739e40 R15: ffff88801d6edb00
FS: 0000000000000000(0000) GS:ffff888125d51000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd1405f6d58 CR3: 000000003478e000 CR4: 00000000003526f0
Call Trace:
sched_balance_newidle+0x693/0xfb0 kernel/sched/fair.c:12864
pick_next_task_fair+0x40/0xba0 kernel/sched/fair.c:8950
__pick_next_task+0xe4/0x450 kernel/sched/core.c:6051
pick_next_task kernel/sched/core.c:-1 [inline]
__schedule+0x6fe/0x4cb0 kernel/sched/core.c:6743
__schedule_loop kernel/sched/core.c:6868 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6883
worker_thread+0xa82/0xda0 kernel/workqueue.c:3417
kthread+0x711/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245