INFO: task syz-executor:5784 blocked for more than 147 seconds.
Not tainted 6.6.100-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D
stack:21640 pid:5784 ppid:1 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5381 [inline]
__schedule+0x14d2/0x44d0 kernel/sched/core.c:6700
schedule+0xbd/0x170 kernel/sched/core.c:6774
wb_wait_for_completion+0x166/0x290 fs/fs-writeback.c:192
sync_inodes_sb+0x1bc/0x9e0 fs/fs-writeback.c:2761
sync_filesystem+0x171/0x220 fs/sync.c:64
generic_shutdown_super+0x6f/0x2b0 fs/super.c:666
kill_block_super+0x44/0x90 fs/super.c:1660
deactivate_locked_super+0x97/0x100 fs/super.c:481
cleanup_mnt+0x429/0x4c0 fs/namespace.c:1250
task_work_run+0x1ce/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177
exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302
do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:87
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fc34f58fcd7
RSP: 002b:00007ffe10c60cc8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007fc34f610b55 RCX: 00007fc34f58fcd7
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffe10c60d80
RBP: 00007ffe10c60d80 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffe10c61e10
R13: 00007fc34f610b55 R14: 000000000001507a R15: 00007ffe10c61e50
Showing all locks held in the system:
2 locks held by kworker/1:0/23:
#0:
ffff888017872538
(
(wq_completion)rcu_gp
){+.+.}-{0:0}
, at: process_one_work kernel/workqueue.c:2609 [inline]
, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
#1:
ffffc900001d7d00
(
(work_completion)(&rew->rew_work)
){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
1 lock held by khungtaskd/29:
#0:
ffffffff8cd2fba0
(rcu_read_lock
){....}-{1:2}
, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline]
, at: rcu_read_lock include/linux/rcupdate.h:786 [inline]
, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633
3 locks held by kworker/u4:4/59:
#0:
ffff88802cf4a938
(
(wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
(wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
#1: ffffc900015a7d00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#1: ffffc900015a7d00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
#2: ffffffff8dfbb188 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xd0/0x14e0 net/ipv6/addrconf.c:4159
2 locks held by kworker/u4:5/193:
#0: ffff88801a27f138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#0: ffff88801a27f138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
#1:
ffffc90002f37d00
(
(work_completion)(&(&wb->dwork)->work)
){+.+.}-{0:0}
, at: process_one_work kernel/workqueue.c:2609 [inline]
, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
3 locks held by kworker/u4:7/1102:
#0:
ffff888017871538
((wq_completion)events_unbound
){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
#1: ffffc900049ffd00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#1: ffffc900049ffd00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
#2: ffffffff8dfbb188 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:286
3 locks held by kworker/0:3/1190:
#0: ffff888017870938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#0: ffff888017870938 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
#1: ffffc9000487fd00 (deferred_process_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#1: ffffc9000487fd00 (deferred_process_work){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
#2: ffffffff8dfbb188 (rtnl_mutex){+.+.}-{3:3}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104
2 locks held by dhcpcd/5452:
#0: ffff88802e942688 (nlk_cb_mutex-ROUTE){+.+.}-{3:3}, at: netlink_dump+0xcc/0xde0 net/netlink/af_netlink.c:2210
#1: ffffffff8dfbb188 (rtnl_mutex){+.+.}-{3:3}, at: netlink_dump+0x71f/0xde0 net/netlink/af_netlink.c:2273
2 locks held by getty/5547:
#0: ffff88802d6c10a0 (
&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1:
ffffc9000327b2f0
(
&ldata->atomic_read_lock
){+.+.}-{3:3}
, at: n_tty_read+0x425/0x1380 drivers/tty/n_tty.c:2217
2 locks held by syz-executor/5784:
#0: ffff88802491a0e0
(&type->s_umount_key
#55
){+.+.}-{3:3}
, at: __super_lock fs/super.c:56 [inline]
, at: __super_lock_excl fs/super.c:71 [inline]
, at: deactivate_super+0xa4/0xe0 fs/super.c:513
#1:
ffff888021a447d0
(
&bdi->wb_switch_rwsem
){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:364 [inline]
){+.+.}-{3:3}, at: sync_inodes_sb+0x1a0/0x9e0 fs/fs-writeback.c:2759
4 locks held by segctord/5891:
5 locks held by kworker/u4:9/6043:
#0: ffff888017873938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#0: ffff888017873938 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
#1: ffffc900054a7d00 (
net_cleanup_work
){+.+.}-{0:0}
, at: process_one_work kernel/workqueue.c:2609 [inline]
, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
#2:
ffffffff8dfae390
(
pernet_ops_rwsem
){++++}-{3:3}
, at: cleanup_net+0x136/0xb90 net/core/net_namespace.c:606
#3:
ffffffff8dfbb188
(
rtnl_mutex
){+.+.}-{3:3}
, at: default_device_exit_batch+0xe9/0xa60 net/core/dev.c:11594
#4:
ffffffff8cd35b78 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:292 [inline]
ffffffff8cd35b78 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x448/0x830 kernel/rcu/tree_exp.h:1004
1 lock held by syz-executor/6276:
#0: ffffffff8dfbb188 (rtnl_mutex){+.+.}-{3:3}
, at: rtnl_lock net/core/rtnetlink.c:78 [inline]
, at: rtnetlink_rcv_msg+0x76f/0xf10 net/core/rtnetlink.c:6472
1 lock held by syz-executor/6290:
#0:
ffffffff8dfbb188
(rtnl_mutex
){+.+.}-{3:3}
, at: rtnl_lock net/core/rtnetlink.c:78 [inline]
, at: rtnetlink_rcv_msg+0x76f/0xf10 net/core/rtnetlink.c:6472
1 lock held by syz-executor/6559:
#0: ffffffff8dfbb188
(
rtnl_mutex){+.+.}-{3:3}
, at: rtnl_lock net/core/rtnetlink.c:78 [inline]
, at: rtnetlink_rcv_msg+0x76f/0xf10 net/core/rtnetlink.c:6472
1 lock held by syz-executor/6617:
#0: ffffffff8dfbb188 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:78 [inline]
#0: ffffffff8dfbb188 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x76f/0xf10 net/core/rtnetlink.c:6472
1 lock held by syz-executor/6624:
#0:
ffffffff8dfbb188
(
rtnl_mutex){+.+.}-{3:3}
, at: rtnl_lock net/core/rtnetlink.c:78 [inline]
, at: rtnetlink_rcv_msg+0x76f/0xf10 net/core/rtnetlink.c:6472
1 lock held by syz.4.113/6629:
#0: ffffffff8dfbb188 (rtnl_mutex){+.+.}-{3:3}, at: do_ipv6_setsockopt+0x3e3/0x3c30 net/ipv6/ipv6_sockglue.c:418
=============================================
NMI backtrace for cpu 1
CPU: 1 PID: 29 Comm: khungtaskd Not tainted 6.6.100-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106
nmi_cpu_backtrace+0x39b/0x3d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x2f0 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline]
watchdog+0xf41/0xf80 kernel/hung_task.c:379
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 11 Comm: kworker/u4:0 Not tainted 6.6.100-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: bat_events batadv_nc_worker
RIP: 0010:get_current arch/x86/include/asm/current.h:41 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:244 [inline]
RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x8/0x90 kernel/kcov.c:313
Code: 08 03 00 00 00 48 89 7c 11 10 48 89 74 11 18 48 89 44 11 20 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 f3 0f 1e fa 48 8b 04 24 <65> 48 8b 15 c0 20 7e 7e 65 8b 0d c1 20 7e 7e 81 e1 00 01 ff 00 74
RSP: 0018:ffffc90000107b58 EFLAGS: 00000246
RAX: ffffffff8a357763 RBX: 0000000000000001 RCX: ffff888019e7bc00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffff88807b92da18 R08: dffffc0000000000 R09: 1ffffffff21b46a4
R10: dffffc0000000000 R11: fffffbfff21b46a5 R12: dffffc0000000000
R13: ffffffff8a357732 R14: ffff888068dd4c80 R15: 0000000000000343
FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055f4b7521000 CR3: 00000000314da000 CR4: 00000000003506f0
Call Trace:
rcu_read_lock include/linux/rcupdate.h:787 [inline]
batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline]
batadv_nc_worker+0x103/0x610 net/batman-adv/network-coding.c:719
process_one_work kernel/workqueue.c:2634 [inline]
process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711
worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293