INFO: task kworker/u8:5:1126 blocked for more than 143 seconds.
Not tainted 6.16.0-rc4-syzkaller-00348-g772b78c2abd8 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:5 state:D stack:25672 pid:1126 tgid:1126 ppid:2 task_flags:0x4208060 flags:0x00004000
Workqueue: netns cleanup_net
Call Trace:
context_switch kernel/sched/core.c:5401 [inline]
__schedule+0x116a/0x5de0 kernel/sched/core.c:6790
__schedule_loop kernel/sched/core.c:6868 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:6883
schedule_timeout+0x257/0x290 kernel/time/sleep_timeout.c:75
do_wait_for_common kernel/sched/completion.c:95 [inline]
__wait_for_common+0x2ff/0x4e0 kernel/sched/completion.c:116
__flush_workqueue+0x3e2/0x1230 kernel/workqueue.c:4002
rds_tcp_listen_stop+0x104/0x150 net/rds/tcp_listen.c:351
rds_tcp_kill_sock net/rds/tcp.c:611 [inline]
rds_tcp_exit_net+0xcb/0x810 net/rds/tcp.c:634
ops_exit_list net/core/net_namespace.c:200 [inline]
ops_undo_list+0x2eb/0xab0 net/core/net_namespace.c:253
cleanup_net+0x408/0x890 net/core/net_namespace.c:686
process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238
process_scheduled_works kernel/workqueue.c:3321 [inline]
worker_thread+0x6c8/0xf10 kernel/workqueue.c:3402
kthread+0x3c5/0x780 kernel/kthread.c:464
ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e5c47c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e5c47c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e5c47c0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6770
3 locks held by kworker/u8:5/1126:
#0: ffff88801c6fe148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213
#1: ffffc900037bfd10 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214
#2: ffffffff9034d5d0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xad/0x890 net/core/net_namespace.c:662
1 lock held by syz-executor/5834:
2 locks held by getty/8116:
#0: ffff888031fe40a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc900041c92f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222
1 lock held by syz.3.752/10024:
#0: ffffffff9034d5d0 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x286/0x5f0 net/core/net_namespace.c:570
1 lock held by syz.1.778/10165:
#0: ffffffff9034d5d0 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x286/0x5f0 net/core/net_namespace.c:570
1 lock held by syz.5.956/11187:
2 locks held by syz.0.960/11217:
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc4-syzkaller-00348-g772b78c2abd8 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x29c/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+0xf70/0x12c0 kernel/hung_task.c:470
kthread+0x3c5/0x780 kernel/kthread.c:464
ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148
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: 10121 Comm: syz-executor Not tainted 6.16.0-rc4-syzkaller-00348-g772b78c2abd8 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:rcu_lock_release include/linux/rcupdate.h:341 [inline]
RIP: 0010:rcu_read_unlock include/linux/rcupdate.h:871 [inline]
RIP: 0010:class_rcu_destructor include/linux/rcupdate.h:1155 [inline]
RIP: 0010:unwind_next_frame+0x3f4/0x20a0 arch/x86/kernel/unwind_orc.c:479
Code: 8e 10 15 00 00 41 c7 45 00 00 00 00 00 31 ed e8 b2 a6 19 0a 85 c0 0f 85 a7 06 00 00 48 c7 c7 c0 47 5c 8e 48 8d 35 00 00 00 00 77 76 2d 00 e8 62 2b 37 00 e9 3d fc ff ff 49 81 ff 00 10 25 92
RSP: 0018:ffffc900193278d0 EFLAGS: 00000202
RAX: 0000000000000001 RBX: ffffc90019327cd8 RCX: ffffc90019328001
RDX: 0000000000000000 RSI: ffffffff816a8ad4 RDI: ffffffff8e5c47c0
RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 00000000000110ac R12: ffffc90019327990
R13: ffffc90019327940 R14: ffffc90019327cd8 R15: ffffc90019327974
FS: 0000000000000000(0000) GS:ffff888124723000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055557ad935c8 CR3: 0000000040292000 CR4: 00000000003526f0
Call Trace:
arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
save_stack+0x160/0x1f0 mm/page_owner.c:156
__reset_page_owner+0x84/0x1a0 mm/page_owner.c:308
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1248 [inline]
__free_frozen_pages+0x7fe/0x1180 mm/page_alloc.c:2706
vfree+0x1fd/0xb50 mm/vmalloc.c:3426
kcov_put kernel/kcov.c:439 [inline]
kcov_put kernel/kcov.c:435 [inline]
kcov_close+0x34/0x60 kernel/kcov.c:535
__fput+0x402/0xb70 fs/file_table.c:465
task_work_run+0x14d/0x240 kernel/task_work.c:227
exit_task_work include/linux/task_work.h:40 [inline]
do_exit+0x86c/0x2bd0 kernel/exit.c:964
do_group_exit+0xd3/0x2a0 kernel/exit.c:1105
__do_sys_exit_group kernel/exit.c:1116 [inline]
__se_sys_exit_group kernel/exit.c:1114 [inline]
__x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1114
x64_sys_call+0x1530/0x1730 arch/x86/include/generated/asm/syscalls_64.h:232
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0x490 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f2f48f8e929
Code: Unable to access opcode bytes at 0x7f2f48f8e8ff.
RSP: 002b:00007ffe847c9968 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007f2f4901231f RCX: 00007f2f48f8e929
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000043
RBP: 00007f2f49012331 R08: 00007ffe847c7707 R09: 00000000000927c0
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000006
R13: 00000000000927c0 R14: 000000000008b4e0 R15: 00007ffe847c9b10