INFO: task syz.2.16948:11222 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.16948 state:D stack:26584 pid:11222 tgid:11221 ppid:6051 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5295 [inline]
__schedule+0x1568/0x5290 kernel/sched/core.c:6907
__schedule_loop kernel/sched/core.c:6989 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7004
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7061
__mutex_lock_common kernel/locking/mutex.c:692 [inline]
__mutex_lock+0x7fe/0x1300 kernel/locking/mutex.c:776
nfsd_nl_threads_set_doit+0x2cb/0x960 fs/nfsd/nfsctl.c:1596
genl_family_rcv_msg_doit+0x22a/0x330 net/netlink/genetlink.c:1115
genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline]
genl_rcv_msg+0x61c/0x7a0 net/netlink/genetlink.c:1210
netlink_rcv_skb+0x232/0x4b0 net/netlink/af_netlink.c:2550
genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219
netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
netlink_unicast+0x80f/0x9b0 net/netlink/af_netlink.c:1344
netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1894
sock_sendmsg_nosec net/socket.c:727 [inline]
__sock_sendmsg net/socket.c:742 [inline]
____sys_sendmsg+0xa68/0xad0 net/socket.c:2592
___sys_sendmsg+0x2a5/0x360 net/socket.c:2646
__sys_sendmsg net/socket.c:2678 [inline]
__do_sys_sendmsg net/socket.c:2683 [inline]
__se_sys_sendmsg net/socket.c:2681 [inline]
__x64_sys_sendmsg+0x1bd/0x2a0 net/socket.c:2681
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f252f39bf79
RSP: 002b:00007f25301cb028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f252f615fa0 RCX: 00007f252f39bf79
RDX: 0000000000008004 RSI: 0000200000000180 RDI: 0000000000000009
RBP: 00007f252f4327e0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f252f616038 R14: 00007f252f615fa0 R15: 00007ffdbc8dc398
Showing all locks held in the system:
1 lock held by khungtaskd/30:
#0: ffffffff8e75e0a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#0: ffffffff8e75e0a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#0: ffffffff8e75e0a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
4 locks held by kworker/u8:7/3458:
#0: ffff88801b6ce948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3250 [inline]
#0: ffff88801b6ce948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0 kernel/workqueue.c:3358
#1: ffffc9000bb2fc40 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline]
#1: ffffc9000bb2fc40 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0 kernel/workqueue.c:3358
#2: ffffffff8fbaffb0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf4/0x800 net/core/net_namespace.c:675
#3: ffffffff8e764200 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x580 kernel/rcu/tree.c:3828
1 lock held by klogd/5180:
2 locks held by getty/5581:
#0: ffff8880362a00a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc900036bb2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0 drivers/tty/n_tty.c:2211
2 locks held by syz.1.16917/11117:
#0: ffffffff8fc2c430 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8ea7eb88 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_threads_set_doit+0x2cb/0x960 fs/nfsd/nfsctl.c:1596
2 locks held by syz.2.16948/11222:
#0: ffffffff8fc2c430 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8ea7eb88 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_threads_set_doit+0x2cb/0x960 fs/nfsd/nfsctl.c:1596
2 locks held by syz.5.17175/11968:
#0: ffffffff8fc2c430 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8ea7eb88 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_threads_set_doit+0x2cb/0x960 fs/nfsd/nfsctl.c:1596
4 locks held by syz.0.17893/14734:
#0: ffffffff8fbaffb0 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x4f7/0x730 net/core/net_namespace.c:577
#1: ffffffff8fbbe808 (rtnl_mutex){+.+.}-{4:4}, at: caif_exit_net+0x6a/0x4a0 net/caif/caif_dev.c:528
#2: ffff888051f57f80 (&caifn->caifdevs.lock){+.+.}-{4:4}, at: caif_exit_net+0x7d/0x4a0 net/caif/caif_dev.c:529
#3: ffffffff8e764338 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline]
#3: ffffffff8e764338 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770 kernel/rcu/tree_exp.h:961
2 locks held by syz.3.17901/14796:
#0: ffffffff8fbaffb0 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x4f7/0x730 net/core/net_namespace.c:577
#1: ffffffff8fbbe808 (rtnl_mutex){+.+.}-{4:4}, at: cfg802154_pernet_exit+0x19/0xe0 net/ieee802154/core.c:351
2 locks held by syz.4.17919/14890:
#0: ffff88807ce64708 (&sb->s_type->i_mutex_key#14){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1028 [inline]
#0: ffff88807ce64708 (&sb->s_type->i_mutex_key#14){+.+.}-{4:4}, at: __sock_release net/socket.c:661 [inline]
#0: ffff88807ce64708 (&sb->s_type->i_mutex_key#14){+.+.}-{4:4}, at: sock_close+0x9b/0x240 net/socket.c:1455
#1: ffffffff8e764338 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline]
#1: ffffffff8e764338 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770 kernel/rcu/tree_exp.h:961
4 locks held by syz.4.17919/14894:
#0: ffffffff8fc2c430 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffff8880793380e8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline]
#1: ffff8880793380e8 (&dev->mutex){....}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:108 [inline]
#1: ffff8880793380e8 (&dev->mutex){....}-{4:4}, at: devlink_get_from_attrs_lock+0x246/0x3b0 net/devlink/netlink.c:198
#2: ffff888069f87250 (&devlink->lock_key#4){+.+.}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:109 [inline]
#2: ffff888069f87250 (&devlink->lock_key#4){+.+.}-{4:4}, at: devlink_get_from_attrs_lock+0x255/0x3b0 net/devlink/netlink.c:198
#3: ffffffff8fbbe808 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#3: ffffffff8fbbe808 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_dev_lock+0x257/0x2f0 net/core/dev.c:2155
1 lock held by syz.7.17920/14897:
#0: ffffffff8fbbe808 (rtnl_mutex){+.+.}-{4:4}, at: __tun_chr_ioctl+0x3bc/0x1e10 drivers/net/tun.c:3078
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:161 [inline]
__sys_info lib/sys_info.c:157 [inline]
sys_info+0x135/0x170 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline]
watchdog+0xf90/0xfe0 kernel/hung_task.c:515
kthread+0x388/0x470 kernel/kthread.c:467
ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
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: 6958 Comm: kworker/u8:0 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
Workqueue: krds_cp_wq#20/0 rds_connect_worker
RIP: 0010:find_stack lib/stackdepot.c:609 [inline]
RIP: 0010:stack_depot_save_flags+0x156/0x810 lib/stackdepot.c:676
Code: c8 31 c5 c1 c0 18 29 c5 48 8b 05 d5 40 76 15 8b 0d c7 40 76 15 21 e9 48 c1 e1 04 4c 8d 24 08 65 ff 05 fe 3a 36 0e 4c 8b 3c 08 <4d> 39 e7 44 89 2c 24 74 05 45 89 d5 eb 34 45 31 ff e9 85 00 00 00
RSP: 0018:ffffc9000c15f708 EFLAGS: 00000282
RAX: ffff88823ae00000 RBX: 1ffff9200182be01 RCX: 000000000016cbc0
RDX: 00000000d161121d RSI: 0000000000000001 RDI: 00000000eaa8a574
RBP: 000000001d216cbc R08: 000000007331748d R09: 00000000bb05f0c3
R10: 000000000000000a R11: ffffffff81af7870 R12: ffff88823af6cbc0
R13: 0000000000002800 R14: ffffc9000c15f7a0 R15: ffff888032503470
FS: 0000000000000000(0000) GS:ffff8881254b0000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd8babe42f8 CR3: 0000000011e22000 CR4: 00000000003526f0
Call Trace:
ref_tracker_free+0x12d/0x840 lib/ref_tracker.c:308
__netns_tracker_free include/net/net_namespace.h:384 [inline]
put_net_track include/net/net_namespace.h:399 [inline]
__sk_destruct+0x3c7/0x880 net/core/sock.c:2379
inet_release+0x143/0x190 net/ipv4/af_inet.c:437
__sock_release net/socket.c:662 [inline]
sock_release+0x85/0x150 net/socket.c:690
rds_tcp_conn_path_connect+0x78c/0x930 net/rds/tcp_connect.c:220
rds_connect_worker+0x1d8/0x290 net/rds/threads.c:176
process_one_work kernel/workqueue.c:3275 [inline]
process_scheduled_works+0xaec/0x17a0 kernel/workqueue.c:3358
worker_thread+0xa50/0xfc0 kernel/workqueue.c:3439
kthread+0x388/0x470 kernel/kthread.c:467
ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245