INFO: task syz.7.973:10083 blocked for more than 144 seconds.
Not tainted 6.14.0-rc5-syzkaller-00023-gbb2281fb05e5 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.7.973 state:D stack:24664 pid:10083 tgid:10076 ppid:9323 task_flags:0x400040 flags:0x00000004
Call Trace:
context_switch kernel/sched/core.c:5378 [inline]
__schedule+0x18bc/0x4c40 kernel/sched/core.c:6765
__schedule_loop kernel/sched/core.c:6842 [inline]
schedule+0x14b/0x320 kernel/sched/core.c:6857
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6914
__mutex_lock_common kernel/locking/mutex.c:662 [inline]
__mutex_lock+0x817/0x1010 kernel/locking/mutex.c:730
nfsd_nl_rpc_status_get_dumpit+0xdf/0x1b70 fs/nfsd/nfsctl.c:1516
genl_dumpit+0x10d/0x1b0 net/netlink/genetlink.c:1027
netlink_dump+0x64d/0xe10 net/netlink/af_netlink.c:2308
__netlink_dump_start+0x5a2/0x790 net/netlink/af_netlink.c:2423
genl_family_rcv_msg_dumpit net/netlink/genetlink.c:1076 [inline]
genl_family_rcv_msg net/netlink/genetlink.c:1192 [inline]
genl_rcv_msg+0x894/0xec0 net/netlink/genetlink.c:1210
netlink_rcv_skb+0x206/0x480 net/netlink/af_netlink.c:2533
genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219
netlink_unicast_kernel net/netlink/af_netlink.c:1312 [inline]
netlink_unicast+0x7f6/0x990 net/netlink/af_netlink.c:1338
netlink_sendmsg+0x8de/0xcb0 net/netlink/af_netlink.c:1882
sock_sendmsg_nosec net/socket.c:718 [inline]
__sock_sendmsg+0x221/0x270 net/socket.c:733
____sys_sendmsg+0x53a/0x860 net/socket.c:2573
___sys_sendmsg net/socket.c:2627 [inline]
__sys_sendmsg+0x269/0x350 net/socket.c:2659
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f04a558d169
RSP: 002b:00007f04a639f038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f04a57a6160 RCX: 00007f04a558d169
RDX: 0000000000000000 RSI: 0000400000000180 RDI: 0000000000000006
RBP: 00007f04a560e2a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f04a57a6160 R15: 00007ffcb036e908
Showing all locks held in the system:
2 locks held by kworker/u8:0/11:
1 lock held by khungtaskd/30:
#0: ffffffff8eb392e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
#0: ffffffff8eb392e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff8eb392e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6746
3 locks held by kworker/u8:3/52:
#0: ffff88814d8da148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88814d8da148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x98b/0x18e0 kernel/workqueue.c:3319
#1: ffffc90000bc7c60 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc90000bc7c60 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9c6/0x18e0 kernel/workqueue.c:3319
#2: ffffffff8fec3708 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:129 [inline]
#2: ffffffff8fec3708 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_verify_work+0x19/0x30 net/ipv6/addrconf.c:4730
3 locks held by kworker/u8:9/3518:
#0: ffff88801b089148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88801b089148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x98b/0x18e0 kernel/workqueue.c:3319
#1: ffffc9000cb87c60 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc9000cb87c60 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9c6/0x18e0 kernel/workqueue.c:3319
#2: ffffffff8fec3708 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:285
1 lock held by klogd/5187:
#0: ffff8880b863e7d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xb0/0x140 kernel/sched/core.c:606
2 locks held by dhcpcd/5492:
#0: ffff88804ff6f6c8 (nlk_cb_mutex-ROUTE){+.+.}-{4:4}, at: __netlink_dump_start+0x119/0x790 net/netlink/af_netlink.c:2387
#1: ffffffff8fec3708 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:79 [inline]
#1: ffffffff8fec3708 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_dumpit+0x99/0x200 net/core/rtnetlink.c:6780
2 locks held by getty/5579:
#0: ffff88803180f0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90002fde2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x616/0x1770 drivers/tty/n_tty.c:2211
1 lock held by syz-executor/5816:
#0: ffff8880b863e7d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xb0/0x140 kernel/sched/core.c:606
1 lock held by syz-executor/5835:
#0: ffffffff8eb3e7b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:334 [inline]
#0: ffffffff8eb3e7b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x451/0x820 kernel/rcu/tree_exp.h:996
2 locks held by syz.2.828/9194:
#0: ffffffff8ff27810 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8ee057e8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0x12d/0x1a90 fs/nfsd/nfsctl.c:1922
3 locks held by syz.7.973/10083:
#0: ffffffff8ff27810 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffff888062e276c8 (nlk_cb_mutex-GENERIC){+.+.}-{4:4}, at: __netlink_dump_start+0x119/0x790 net/netlink/af_netlink.c:2387
#2: ffffffff8ee057e8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_rpc_status_get_dumpit+0xdf/0x1b70 fs/nfsd/nfsctl.c:1516
2 locks held by syz-executor/11064:
#0: ffffffff8f664800 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
#0: ffffffff8f664800 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff8f664800 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x22/0x250 net/core/rtnetlink.c:564
#1: ffffffff8fec3708 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:79 [inline]
#1: ffffffff8fec3708 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:335 [inline]
#1: ffffffff8fec3708 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0xc55/0x1d30 net/core/rtnetlink.c:4021
2 locks held by dhcpcd/11332:
#0: ffff88805b79e208 (&sb->s_type->i_mutex_key#9){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:877 [inline]
#0: ffff88805b79e208 (&sb->s_type->i_mutex_key#9){+.+.}-{4:4}, at: __sock_release net/socket.c:646 [inline]
#0: ffff88805b79e208 (&sb->s_type->i_mutex_key#9){+.+.}-{4:4}, at: sock_close+0x90/0x240 net/socket.c:1398
#1: ffffffff8eb3e7b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:334 [inline]
#1: ffffffff8eb3e7b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x451/0x820 kernel/rcu/tree_exp.h:996
1 lock held by dhcpcd/11333:
#0: ffff88805b79f408 (&sb->s_type->i_mutex_key#9){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:877 [inline]
#0: ffff88805b79f408 (&sb->s_type->i_mutex_key#9){+.+.}-{4:4}, at: __sock_release net/socket.c:646 [inline]
#0: ffff88805b79f408 (&sb->s_type->i_mutex_key#9){+.+.}-{4:4}, at: sock_close+0x90/0x240 net/socket.c:1398
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.14.0-rc5-syzkaller-00023-gbb2281fb05e5 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:236 [inline]
watchdog+0x1058/0x10a0 kernel/hung_task.c:399
kthread+0x7a9/0x920 kernel/kthread.c:464
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 11064 Comm: syz-executor Not tainted 6.14.0-rc5-syzkaller-00023-gbb2281fb05e5 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:io_serial_in+0x76/0xb0 drivers/tty/serial/8250/8250_port.c:409
Code: b0 a3 45 fc 89 e9 41 d3 e6 48 83 c3 40 48 89 d8 48 c1 e8 03 42 80 3c 38 00 74 08 48 89 df e8 d1 57 aa fc 44 03 33 44 89 f2 ec <0f> b6 c0 5b 41 5e 41 5f 5d c3 cc cc cc cc 89 e9 80 e1 07 38 c1 7c
RSP: 0018:ffffc90002f867f8 EFLAGS: 00000002
RAX: 1ffffffff352c100 RBX: ffffffff9a960e60 RCX: 0000000000000000
RDX: 00000000000003fd RSI: 0000000000000000 RDI: 0000000000000020
RBP: 0000000000000000 R08: ffffffff857c2b06 R09: 1ffff110049e4046
R10: dffffc0000000000 R11: ffffffff857c2ac0 R12: 0000000000000020
R13: 1ffffffff352c21e R14: 00000000000003fd R15: dffffc0000000000
FS: 000055555c647500(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055ebdef30680 CR3: 0000000062868000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 00000000ffff000b DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
serial_in drivers/tty/serial/8250/8250.h:137 [inline]
serial_lsr_in drivers/tty/serial/8250/8250.h:159 [inline]
wait_for_lsr+0x1b1/0x320 drivers/tty/serial/8250/8250_port.c:2100
fifo_wait_for_lsr drivers/tty/serial/8250/8250_port.c:3357 [inline]
serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3380 [inline]
serial8250_console_write+0x134c/0x1e00 drivers/tty/serial/8250/8250_port.c:3465
console_emit_next_record kernel/printk/printk.c:3122 [inline]
console_flush_all+0x869/0xeb0 kernel/printk/printk.c:3210
__console_flush_and_unlock kernel/printk/printk.c:3269 [inline]
console_unlock+0x14f/0x3b0 kernel/printk/printk.c:3309
vprintk_emit+0x730/0xa10 kernel/printk/printk.c:2432
_printk+0xd5/0x120 kernel/printk/printk.c:2457
start_creating+0x2a9/0x310
debugfs_create_dir+0x25/0x430 fs/debugfs/inode.c:586
hsr_debugfs_init+0x2e/0x100 net/hsr/hsr_debugfs.c:78
hsr_dev_finalize+0x88f/0xa20 net/hsr/hsr_device.c:773
hsr_newlink+0x7ee/0x970 net/hsr/hsr_netlink.c:120
rtnl_newlink_create+0x2ee/0xa40 net/core/rtnetlink.c:3796
__rtnl_newlink net/core/rtnetlink.c:3907 [inline]
rtnl_newlink+0x17cc/0x1d30 net/core/rtnetlink.c:4022
rtnetlink_rcv_msg+0x791/0xcf0 net/core/rtnetlink.c:6912
netlink_rcv_skb+0x206/0x480 net/netlink/af_netlink.c:2533
netlink_unicast_kernel net/netlink/af_netlink.c:1312 [inline]
netlink_unicast+0x7f6/0x990 net/netlink/af_netlink.c:1338
netlink_sendmsg+0x8de/0xcb0 net/netlink/af_netlink.c:1882
sock_sendmsg_nosec net/socket.c:718 [inline]
__sock_sendmsg+0x221/0x270 net/socket.c:733
__sys_sendto+0x363/0x4c0 net/socket.c:2187
__do_sys_sendto net/socket.c:2194 [inline]
__se_sys_sendto net/socket.c:2190 [inline]
__x64_sys_sendto+0xde/0x100 net/socket.c:2190
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7ba078effc
Code: 2a 5f 02 00 44 8b 4c 24 2c 4c 8b 44 24 20 89 c5 44 8b 54 24 28 48 8b 54 24 18 b8 2c 00 00 00 48 8b 74 24 10 8b 7c 24 08 0f 05 <48> 3d 00 f0 ff ff 77 34 89 ef 48 89 44 24 08 e8 70 5f 02 00 48 8b
RSP: 002b:00007ffc90c9fa60 EFLAGS: 00000293 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f7ba14d4620 RCX: 00007f7ba078effc
RDX: 0000000000000048 RSI: 00007f7ba14d4670 RDI: 0000000000000003
RBP: 0000000000000000 R08: 00007ffc90c9fab4 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000003
R13: 0000000000000000 R14: 00007f7ba14d4670 R15: 0000000000000000