INFO: task kworker/u8:8:1138 blocked for more than 143 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:8 state:D stack:24456 pid:1138 tgid:1138 ppid:2 task_flags:0x4208060 flags:0x00080000
Workqueue: netns cleanup_net
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x1139/0x6150 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:6960
schedule_timeout+0x257/0x290 kernel/time/sleep_timeout.c:75
do_wait_for_common kernel/sched/completion.c:100 [inline]
__wait_for_common+0x2fc/0x4e0 kernel/sched/completion.c:121
__flush_workqueue+0x3e2/0x1230 kernel/workqueue.c:4033
rxrpc_destroy_all_connections+0xed/0x440 net/rxrpc/conn_object.c:477
rxrpc_exit_net+0x7b/0xc0 net/rxrpc/net_ns.c:113
ops_exit_list net/core/net_namespace.c:199 [inline]
ops_undo_list+0x2ee/0xab0 net/core/net_namespace.c:252
cleanup_net+0x41b/0x830 net/core/net_namespace.c:696
process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3257
process_scheduled_works kernel/workqueue.c:3340 [inline]
worker_thread+0x6c8/0xf10 kernel/workqueue.c:3421
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
INFO: task syz.0.55:6187 blocked for more than 144 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.55 state:D stack:26600 pid:6187 tgid:6182 ppid:5839 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x1139/0x6150 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:6960
schedule_timeout+0x257/0x290 kernel/time/sleep_timeout.c:75
do_wait_for_common kernel/sched/completion.c:100 [inline]
__wait_for_common+0x2fc/0x4e0 kernel/sched/completion.c:121
__flush_workqueue+0x3e2/0x1230 kernel/workqueue.c:4033
rxrpc_release_sock net/rxrpc/af_rxrpc.c:965 [inline]
rxrpc_release+0x2a7/0x6a0 net/rxrpc/af_rxrpc.c:996
__sock_release net/socket.c:662 [inline]
sock_release+0x91/0x1d0 net/socket.c:690
afs_open_socket+0x334/0x400 fs/afs/rxrpc.c:117
afs_net_init+0x825/0xb00 fs/afs/main.c:116
ops_init+0x1e2/0x5f0 net/core/net_namespace.c:137
setup_net+0x11d/0x3a0 net/core/net_namespace.c:446
copy_net_ns+0x351/0x7c0 net/core/net_namespace.c:581
create_new_namespaces+0x3ea/0xab0 kernel/nsproxy.c:130
unshare_nsproxy_namespaces+0xc0/0x1f0 kernel/nsproxy.c:226
ksys_unshare+0x45b/0xa40 kernel/fork.c:3171
__do_sys_unshare kernel/fork.c:3242 [inline]
__se_sys_unshare kernel/fork.c:3240 [inline]
__x64_sys_unshare+0x31/0x40 kernel/fork.c:3240
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8ef978f7c9
RSP: 002b:00007f8efa658038 EFLAGS: 00000246 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007f8ef99e6090 RCX: 00007f8ef978f7c9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000080
RBP: 00007f8ef9813f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8ef99e6128 R14: 00007f8ef99e6090 R15: 00007ffe3ca57e68
Showing all locks held in the system:
1 lock held by rcu_exp_gp_kthr/18:
#0: ffff8880b843add8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:647 [inline]
#0: ffff8880b843add8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x7e/0x130 kernel/sched/core.c:632
1 lock held by khungtaskd/31:
#0: ffffffff8e3c9520 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e3c9520 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8e3c9520 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6775
3 locks held by kworker/u8:8/1138:
#0: ffff88801badf148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x128d/0x1b20 kernel/workqueue.c:3232
#1: ffffc9000419fc90 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x914/0x1b20 kernel/workqueue.c:3233
#2: ffffffff9012e9d0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xad/0x830 net/core/net_namespace.c:670
2 locks held by getty/5592:
#0: ffff8880310cd0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x1510 drivers/tty/n_tty.c:2211
1 lock held by syz.0.55/6187:
#0: ffffffff9012e9d0 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x333/0x7c0 net/core/net_namespace.c:577
1 lock held by syz.2.207/6944:
#0: ffffffff9012e9d0 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x333/0x7c0 net/core/net_namespace.c:577
1 lock held by syz.4.292/7323:
#0: ffff888043b31348 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1027 [inline]
#0: ffff888043b31348 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: __sock_release+0x86/0x270 net/socket.c:661
1 lock held by syz.5.348/7574:
#0: ffffffff9012e9d0 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x333/0x7c0 net/core/net_namespace.c:577
3 locks held by kworker/1:8/7966:
#0: ffff88813ff55948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x128d/0x1b20 kernel/workqueue.c:3232
#1: ffffc9000bf57c90 (free_ipc_work){+.+.}-{0:0}, at: process_one_work+0x914/0x1b20 kernel/workqueue.c:3233
#2: ffffffff8e3d4c78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x284/0x3c0 kernel/rcu/tree_exp.h:311
1 lock held by syz.3.458/8118:
#0: ffff88803ba5e3c8 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1027 [inline]
#0: ffff88803ba5e3c8 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: __sock_release+0x86/0x270 net/socket.c:661
1 lock held by syz.3.458/8120:
#0: ffff88803ba62488 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1027 [inline]
#0: ffff88803ba62488 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: __sock_release+0x86/0x270 net/socket.c:661
1 lock held by syz.7.488/8305:
#0: ffffffff9012e9d0 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x333/0x7c0 net/core/net_namespace.c:577
1 lock held by syz.6.512/8414:
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
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:160 [inline]
__sys_info lib/sys_info.c:157 [inline]
sys_info+0x133/0x180 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline]
watchdog+0xe66/0x1180 kernel/hung_task.c:515
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 7913 Comm: syz.1.413 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:__kernel_text_address+0x32/0x40 kernel/extable.c:92
Code: e8 e3 fe ff ff 85 c0 75 1b 48 81 fb 00 60 06 92 72 0c 31 c0 48 81 fb ca 91 28 92 0f 92 c0 5b e9 14 c9 f2 09 b8 01 00 00 00 5b 09 c9 f2 09 66 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90
RSP: 0018:ffffc9000be176c0 EFLAGS: 00000202
RAX: 0000000000000001 RBX: ffffc9000be176e0 RCX: ffffc9000be17634
RDX: 1ffff920017c2ee5 RSI: ffffffff8daa458e RDI: ffffffff81000130
RBP: ffffc9000be17728 R08: 0000000000000001 R09: 00000000ffffffff
R10: 0000000000000002 R11: 00000000000a74e5 R12: ffffffff81a8fa00
R13: ffffc9000be177a0 R14: 0000000000000000 R15: ffff888026071e80
FS: 0000000000000000(0000) GS:ffff8881249fc000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000557faf06d000 CR3: 0000000035934000 CR4: 00000000003526f0
Call Trace:
unwind_get_return_address+0x59/0xa0 arch/x86/kernel/unwind_orc.c:385
arch_stack_walk+0xa6/0x100 arch/x86/kernel/stacktrace.c:26
stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
save_stack+0x160/0x1f0 mm/page_owner.c:165
__reset_page_owner+0x84/0x1a0 mm/page_owner.c:320
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1406 [inline]
__free_frozen_pages+0x7df/0x1170 mm/page_alloc.c:2943
vfree+0x1fd/0xb50 mm/vmalloc.c:3466
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:468
task_work_run+0x150/0x240 kernel/task_work.c:233
exit_task_work include/linux/task_work.h:40 [inline]
do_exit+0x87f/0x2bd0 kernel/exit.c:971
do_group_exit+0xd3/0x2a0 kernel/exit.c:1112
get_signal+0x2671/0x26d0 kernel/signal.c:3034
arch_do_signal_or_restart+0x8f/0x7a0 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:41 [inline]
exit_to_user_mode_loop+0x8c/0x540 kernel/entry/common.c:75
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline]
do_syscall_64+0x4ee/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5c03bc2085
Code: Unable to access opcode bytes at 0x7f5c03bc205b.
RSP: 002b:00007f5c049d5f80 EFLAGS: 00000293 ORIG_RAX: 00000000000000e6
RAX: fffffffffffffdfc RBX: 00007f5c03de6090 RCX: 00007f5c03bc2085
RDX: 00007f5c049d5fc0 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f5c03c13f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000
R13: 00007f5c03de6128 R14: 00007f5c03de6090 R15: 00007ffc3fff9838