2022-04-26 18:13:45

by Wang Hai

[permalink] [raw]
Subject: [PATCH net] SUNRPC: Fix local socket leak in xs_local_setup_socket()

If the connection to a local endpoint in xs_local_setup_socket() fails,
fput() is missing in the error path, which will result in a socket leak.
It can be reproduced in simple script below.

while true
do
systemctl stop rpcbind.service
systemctl stop rpc-statd.service
systemctl stop nfs-server.service

systemctl restart rpcbind.service
systemctl restart rpc-statd.service
systemctl restart nfs-server.service
done

When executing the script, you can observe that the
"cat /proc/net/unix | wc -l" count keeps growing.

Add the missing fput(), and restore transport to old socket.

Signed-off-by: Wang Hai <[email protected]>
---
net/sunrpc/xprtsock.c | 20 ++++++++++++++++++--
1 file changed, 18 insertions(+), 2 deletions(-)

diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c
index 0f39e08ee580..7219c545385e 100644
--- a/net/sunrpc/xprtsock.c
+++ b/net/sunrpc/xprtsock.c
@@ -1819,6 +1819,9 @@ static int xs_local_finish_connecting(struct rpc_xprt *xprt,
{
struct sock_xprt *transport = container_of(xprt, struct sock_xprt,
xprt);
+ struct socket *trans_sock = NULL;
+ struct sock *trans_inet = NULL;
+ int ret;

if (!transport->inet) {
struct sock *sk = sock->sk;
@@ -1835,6 +1838,9 @@ static int xs_local_finish_connecting(struct rpc_xprt *xprt,

xprt_clear_connected(xprt);

+ trans_sock = transport->sock;
+ trans_inet = transport->inet;
+
/* Reset to new socket */
transport->sock = sock;
transport->inet = sk;
@@ -1844,7 +1850,14 @@ static int xs_local_finish_connecting(struct rpc_xprt *xprt,

xs_stream_start_connect(transport);

- return kernel_connect(sock, xs_addr(xprt), xprt->addrlen, 0);
+ ret = kernel_connect(sock, xs_addr(xprt), xprt->addrlen, 0);
+ /* Restore to old socket */
+ if (ret && trans_inet) {
+ transport->sock = trans_sock;
+ transport->inet = trans_inet;
+ }
+
+ return ret;
}

/**
@@ -1887,7 +1900,7 @@ static int xs_local_setup_socket(struct sock_xprt *transport)
xprt->stat.connect_time += (long)jiffies -
xprt->stat.connect_start;
xprt_set_connected(xprt);
- break;
+ goto out;
case -ENOBUFS:
break;
case -ENOENT:
@@ -1904,6 +1917,9 @@ static int xs_local_setup_socket(struct sock_xprt *transport)
xprt->address_strings[RPC_DISPLAY_ADDR]);
}

+ transport->file = NULL;
+ fput(filp);
+
out:
xprt_clear_connecting(xprt);
xprt_wake_pending_tasks(xprt, status);
--
2.17.1


2022-04-26 19:08:25

by Trond Myklebust

[permalink] [raw]
Subject: Re: [PATCH net] SUNRPC: Fix local socket leak in xs_local_setup_socket()

On Tue, 2022-04-26 at 21:20 +0800, Wang Hai wrote:
> If the connection to a local endpoint in xs_local_setup_socket()
> fails,
> fput() is missing in the error path, which will result in a socket
> leak.
> It can be reproduced in simple script below.
>
> while true
> do
>         systemctl stop rpcbind.service
>         systemctl stop rpc-statd.service
>         systemctl stop nfs-server.service
>
>         systemctl restart rpcbind.service
>         systemctl restart rpc-statd.service
>         systemctl restart nfs-server.service
> done
>
> When executing the script, you can observe that the
> "cat /proc/net/unix | wc -l" count keeps growing.
>
> Add the missing fput(), and restore transport to old socket.
>
> Signed-off-by: Wang Hai <[email protected]>
> ---
>  net/sunrpc/xprtsock.c | 20 ++++++++++++++++++--
>  1 file changed, 18 insertions(+), 2 deletions(-)
>
> diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c
> index 0f39e08ee580..7219c545385e 100644
> --- a/net/sunrpc/xprtsock.c
> +++ b/net/sunrpc/xprtsock.c
> @@ -1819,6 +1819,9 @@ static int xs_local_finish_connecting(struct
> rpc_xprt *xprt,
>  {
>         struct sock_xprt *transport = container_of(xprt, struct
> sock_xprt,
>                                                                      
>    xprt);
> +       struct socket *trans_sock = NULL;
> +       struct sock *trans_inet = NULL;
> +       int ret;
>  
>         if (!transport->inet) {
>                 struct sock *sk = sock->sk;
> @@ -1835,6 +1838,9 @@ static int xs_local_finish_connecting(struct
> rpc_xprt *xprt,
>  
>                 xprt_clear_connected(xprt);
>  
> +               trans_sock = transport->sock;
> +               trans_inet = transport->inet;
> +

Both values are NULL here

>                 /* Reset to new socket */
>                 transport->sock = sock;
>                 transport->inet = sk;
> @@ -1844,7 +1850,14 @@ static int xs_local_finish_connecting(struct
> rpc_xprt *xprt,
>  
>         xs_stream_start_connect(transport);
>  
> -       return kernel_connect(sock, xs_addr(xprt), xprt->addrlen, 0);
> +       ret = kernel_connect(sock, xs_addr(xprt), xprt->addrlen, 0);
> +       /* Restore to old socket */
> +       if (ret && trans_inet) {
> +               transport->sock = trans_sock;
> +               transport->inet = trans_inet;
> +       }
> +
> +       return ret;
>  }
>  
>  /**
> @@ -1887,7 +1900,7 @@ static int xs_local_setup_socket(struct
> sock_xprt *transport)
>                 xprt->stat.connect_time += (long)jiffies -
>                                            xprt->stat.connect_start;
>                 xprt_set_connected(xprt);
> -               break;
> +               goto out;
>         case -ENOBUFS:
>                 break;
>         case -ENOENT:
> @@ -1904,6 +1917,9 @@ static int xs_local_setup_socket(struct
> sock_xprt *transport)
>                                 xprt-
> >address_strings[RPC_DISPLAY_ADDR]);
>         }
>  
> +       transport->file = NULL;
> +       fput(filp);

Please just call xprt_force_disconnect() so that this can be cleaned up
from a safe context.

> +
>  out:
>         xprt_clear_connecting(xprt);
>         xprt_wake_pending_tasks(xprt, status);

--
Trond Myklebust
Linux NFS client maintainer, Hammerspace
[email protected]


2022-04-27 09:46:36

by Wang Hai

[permalink] [raw]
Subject: Re: [PATCH net] SUNRPC: Fix local socket leak in xs_local_setup_socket()


在 2022/4/27 2:51, Trond Myklebust 写道:
> On Tue, 2022-04-26 at 21:20 +0800, Wang Hai wrote:
>> If the connection to a local endpoint in xs_local_setup_socket()
>> fails,
>> fput() is missing in the error path, which will result in a socket
>> leak.
>> It can be reproduced in simple script below.
>>
>> while true
>> do
>>         systemctl stop rpcbind.service
>>         systemctl stop rpc-statd.service
>>         systemctl stop nfs-server.service
>>
>>         systemctl restart rpcbind.service
>>         systemctl restart rpc-statd.service
>>         systemctl restart nfs-server.service
>> done
>>
>> When executing the script, you can observe that the
>> "cat /proc/net/unix | wc -l" count keeps growing.
>>
>> Add the missing fput(), and restore transport to old socket.
>>
>> Signed-off-by: Wang Hai <[email protected]>
>> ---
>>  net/sunrpc/xprtsock.c | 20 ++++++++++++++++++--
>>  1 file changed, 18 insertions(+), 2 deletions(-)
>>
>> diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c
>> index 0f39e08ee580..7219c545385e 100644
>> --- a/net/sunrpc/xprtsock.c
>> +++ b/net/sunrpc/xprtsock.c
>> @@ -1819,6 +1819,9 @@ static int xs_local_finish_connecting(struct
>> rpc_xprt *xprt,
>>  {
>>         struct sock_xprt *transport = container_of(xprt, struct
>> sock_xprt,
>>
>>    xprt);
>> +       struct socket *trans_sock = NULL;
>> +       struct sock *trans_inet = NULL;
>> +       int ret;
>>
>>         if (!transport->inet) {
>>                 struct sock *sk = sock->sk;
>> @@ -1835,6 +1838,9 @@ static int xs_local_finish_connecting(struct
>> rpc_xprt *xprt,
>>
>>                 xprt_clear_connected(xprt);
>>
>> +               trans_sock = transport->sock;
>> +               trans_inet = transport->inet;
>> +
> Both values are NULL here
Got it, thanks
>
>>                 /* Reset to new socket */
>>                 transport->sock = sock;
>>                 transport->inet = sk;
>> @@ -1844,7 +1850,14 @@ static int xs_local_finish_connecting(struct
>> rpc_xprt *xprt,
>>
>>         xs_stream_start_connect(transport);
>>
>> -       return kernel_connect(sock, xs_addr(xprt), xprt->addrlen, 0);
>> +       ret = kernel_connect(sock, xs_addr(xprt), xprt->addrlen, 0);
>> +       /* Restore to old socket */
>> +       if (ret && trans_inet) {
>> +               transport->sock = trans_sock;
>> +               transport->inet = trans_inet;
>> +       }
>> +
>> +       return ret;
>>  }
>>
>>  /**
>> @@ -1887,7 +1900,7 @@ static int xs_local_setup_socket(struct
>> sock_xprt *transport)
>>                 xprt->stat.connect_time += (long)jiffies -
>>                                            xprt->stat.connect_start;
>>                 xprt_set_connected(xprt);
>> -               break;
>> +               goto out;
>>         case -ENOBUFS:
>>                 break;
>>         case -ENOENT:
>> @@ -1904,6 +1917,9 @@ static int xs_local_setup_socket(struct
>> sock_xprt *transport)
>>                                 xprt-
>>> address_strings[RPC_DISPLAY_ADDR]);
>>         }
>>
>> +       transport->file = NULL;
>> +       fput(filp);
> Please just call xprt_force_disconnect() so that this can be cleaned up
> from a safe context.

Hi, Trond

Thank you for your advice, I tried this, but it doesn't seem to

work and an error is reported. I'll analyze why this happens

diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c
index 0f39e08ee580..3d1387b2cfbf 100644
--- a/net/sunrpc/xprtsock.c
+++ b/net/sunrpc/xprtsock.c
@@ -1887,7 +1887,7 @@ static int xs_local_setup_socket(struct sock_xprt
*transport)
                xprt->stat.connect_time += (long)jiffies -
xprt->stat.connect_start;
                xprt_set_connected(xprt);
-               break;
+               goto out;
        case -ENOBUFS:
                break;
        case -ENOENT:
@@ -1904,6 +1904,8 @@ static int xs_local_setup_socket(struct sock_xprt
*transport)
xprt->address_strings[RPC_DISPLAY_ADDR]);
        }

+       xprt_force_disconnect(xprt);
+
 out:
        xprt_clear_connecting(xprt);
        xprt_wake_pending_tasks(xprt, status);


[ 2541.763895][ T8289] ------------[ cut here ]------------
[ 2541.765829][ T8289] WARNING: CPU: 0 PID: 8289 at
kernel/workqueue.c:1499 __queue_work+0x72a/0x810
[ 2541.768862][ T8289] Modules linked in:
[ 2541.770085][ T8289] CPU: 0 PID: 8289 Comm: gssproxy Tainted: G       
W         5.17.0+ #762
[ 2541.772724][ T8289] Hardware name: QEMU Standard PC (i440FX + PIIX,
1996), BIOS 1.10.2-1ubuntu1 04/01/2014
[ 2541.773788][ T8289] RIP: 0010:__queue_work+0x72a/0x810
[ 2541.773788][ T8289] Code: 48 c7 c7 f8 7b b8 84 c6 05 b1 f4 39 04 01
e8 ad 65 05 00 e9 7f fe ff ff e8 33 94 11 00 4c 8b 33 e9 ff f9 ff ff e8
26 94 11 00 <0f> 0b e9 d2 fa ff ff e8 1a 94 11 00 4c 8d 7b 68 41 83 cc
02 e9 aa
[ 2541.773788][ T8289] RSP: 0018:ffffc900083dfb20 EFLAGS: 00010093
[ 2541.773788][ T8289] RAX: 0000000000000000 RBX: ffff8881002a7900 RCX:
0000000000000000
[ 2541.773788][ T8289] RDX: ffff88824e091b40 RSI: ffffffff8119be6a RDI:
ffffc900083dfb07
[ 2541.773788][ T8289] RBP: ffffc900083dfb60 R08: 0000000000000001 R09:
0000000000000000
[ 2541.773788][ T8289] R10: 0000000000000000 R11: 6e75732f74656e5b R12:
0000000000000000
[ 2541.773788][ T8289] R13: ffff88811a284668 R14: ffff888237c2d440 R15:
ffff888243141c00
[ 2541.773788][ T8289] FS:  00007f3bb3f9dc40(0000)
GS:ffff888237c00000(0000) knlGS:0000000000000000
[ 2541.773788][ T8289] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 2541.773788][ T8289] CR2: 00007f3bb04a72e0 CR3: 00000002602c5000 CR4:
00000000000006f0
[ 2541.773788][ T8289] DR0: 0000000000000000 DR1: 0000000000000000 DR2:
0000000000000000
[ 2541.773788][ T8289] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7:
0000000000000400
[ 2541.773788][ T8289] Call Trace:
[ 2541.773788][ T8289]  <TASK>
[ 2541.773788][ T8289]  queue_work_on+0x88/0x90
[ 2541.773788][ T8289]  xprt_schedule_autoclose_locked+0x7a/0xb0
[ 2541.773788][ T8289]  xprt_force_disconnect+0x53/0x150
[ 2541.773788][ T8289]  xs_local_setup_socket+0x131/0x3e0
[ 2541.823215][ T8289]  xs_setup_local+0x24b/0x280
[ 2541.823215][ T8289]  xprt_create_transport+0xb0/0x340
[ 2541.823215][ T8289]  rpc_create+0x104/0x2b0
[ 2541.823215][ T8289]  gssp_rpc_create+0x93/0xe0
[ 2541.823215][ T8289]  set_gssp_clnt+0xd9/0x230
[ 2541.823215][ T8289]  write_gssp+0xb9/0x130
[ 2541.823215][ T8289]  ? lock_acquire+0x1de/0x2f0
[ 2541.823215][ T8289]  proc_reg_write+0xd2/0x110
[ 2541.823215][ T8289]  ? set_gss_proxy+0x1d0/0x1d0
[ 2541.823215][ T8289]  ? proc_reg_compat_ioctl+0x100/0x100
[ 2541.823215][ T8289]  vfs_write+0x11d/0x4b0
[ 2541.841496][ T8289]  ksys_write+0xe0/0x130
[ 2541.841496][ T8289]  __x64_sys_write+0x23/0x30
[ 2541.841496][ T8289]  do_syscall_64+0x34/0xb0
[ 2541.841496][ T8289]  entry_SYSCALL_64_after_hwframe+0x44/0xae
[ 2541.841496][ T8289] RIP: 0033:0x7f3bb0811280
[ 2541.841496][ T8289] Code: 00 c3 0f 1f 84 00 00 00 00 00 48 8b 05 c1
8c 20 00 c3 0f 1f 84 00 00 00 00 00 83 3d 09 cf 20 00 00 75 10 b8 01 00
00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 6e fd ff ff 48
89 04 24
[ 2541.841496][ T8289] RSP: 002b:00007ffc59024c98 EFLAGS: 00000246
ORIG_RAX: 0000000000000001
[ 2541.841496][ T8289] RAX: ffffffffffffffda RBX: 0000000000000009 RCX:
00007f3bb0811280
[ 2541.841496][ T8289] RDX: 0000000000000001 RSI: 00007ffc59024ca6 RDI:
0000000000000009
[ 2541.841496][ T8289] RBP: 0000000000000000 R08: 0000000000000020 R09:
0000000000000060
[ 2541.841496][ T8289] R10: 0000561545627900 R11: 0000000000000246 R12:
0000561545630580
[ 2541.841496][ T8289] R13: 00007ffc59024fd0 R14: 0000000000000000 R15:
0000000000000000
[ 2541.841496][ T8289]  </TASK>
[ 2541.841496][ T8289] irq event stamp: 0
[ 2541.841496][ T8289] hardirqs last  enabled at (0):
[<0000000000000000>] 0x0
[ 2541.841496][ T8289] hardirqs last disabled at (0):
[<ffffffff81165e25>] copy_process+0xb35/0x2410
[ 2541.841496][ T8289] softirqs last  enabled at (0):
[<ffffffff81165e25>] copy_process+0xb35/0x2410
[ 2541.841496][ T8289] softirqs last disabled at (0):
[<0000000000000000>] 0x0
[ 2541.841496][ T8289] ---[ end trace 0000000000000000 ]---
>> +
>>  out:
>>         xprt_clear_connecting(xprt);
>>         xprt_wake_pending_tasks(xprt, status);

--
Wang Hai

2022-04-28 14:36:22

by Wang Hai

[permalink] [raw]
Subject: Re: [PATCH net] SUNRPC: Fix local socket leak in xs_local_setup_socket()


在 2022/4/27 15:15, wanghai (M) 写道:
>
> 在 2022/4/27 2:51, Trond Myklebust 写道:
>> On Tue, 2022-04-26 at 21:20 +0800, Wang Hai wrote:
>>> If the connection to a local endpoint in xs_local_setup_socket()
>>> fails,
>>> fput() is missing in the error path, which will result in a socket
>>> leak.
>>> It can be reproduced in simple script below.
>>>
>>> while true
>>> do
>>>          systemctl stop rpcbind.service
>>>          systemctl stop rpc-statd.service
>>>          systemctl stop nfs-server.service
>>>
>>>          systemctl restart rpcbind.service
>>>          systemctl restart rpc-statd.service
>>>          systemctl restart nfs-server.service
>>> done
>>>
>>> When executing the script, you can observe that the
>>> "cat /proc/net/unix | wc -l" count keeps growing.
>>>
>>> Add the missing fput(), and restore transport to old socket.
>>>
>>> Signed-off-by: Wang Hai <[email protected]>
>>> ---
>>>   net/sunrpc/xprtsock.c | 20 ++++++++++++++++++--
>>>   1 file changed, 18 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c
>>> index 0f39e08ee580..7219c545385e 100644
>>> --- a/net/sunrpc/xprtsock.c
>>> +++ b/net/sunrpc/xprtsock.c
>>> @@ -1819,6 +1819,9 @@ static int xs_local_finish_connecting(struct
>>> rpc_xprt *xprt,
>>>   {
>>>          struct sock_xprt *transport = container_of(xprt, struct
>>> sock_xprt,
>>>     xprt);
>>> +       struct socket *trans_sock = NULL;
>>> +       struct sock *trans_inet = NULL;
>>> +       int ret;
>>>            if (!transport->inet) {
>>>                  struct sock *sk = sock->sk;
>>> @@ -1835,6 +1838,9 @@ static int xs_local_finish_connecting(struct
>>> rpc_xprt *xprt,
>>>                    xprt_clear_connected(xprt);
>>>   +               trans_sock = transport->sock;
>>> +               trans_inet = transport->inet;
>>> +
>> Both values are NULL here
> Got it, thanks
>>
>>>                  /* Reset to new socket */
>>>                  transport->sock = sock;
>>>                  transport->inet = sk;
>>> @@ -1844,7 +1850,14 @@ static int xs_local_finish_connecting(struct
>>> rpc_xprt *xprt,
>>>            xs_stream_start_connect(transport);
>>>   -       return kernel_connect(sock, xs_addr(xprt), xprt->addrlen, 0);
>>> +       ret = kernel_connect(sock, xs_addr(xprt), xprt->addrlen, 0);
>>> +       /* Restore to old socket */
>>> +       if (ret && trans_inet) {
>>> +               transport->sock = trans_sock;
>>> +               transport->inet = trans_inet;
>>> +       }
>>> +
>>> +       return ret;
>>>   }
>>>     /**
>>> @@ -1887,7 +1900,7 @@ static int xs_local_setup_socket(struct
>>> sock_xprt *transport)
>>>                  xprt->stat.connect_time += (long)jiffies -
>>> xprt->stat.connect_start;
>>>                  xprt_set_connected(xprt);
>>> -               break;
>>> +               goto out;
>>>          case -ENOBUFS:
>>>                  break;
>>>          case -ENOENT:
>>> @@ -1904,6 +1917,9 @@ static int xs_local_setup_socket(struct
>>> sock_xprt *transport)
>>>                                  xprt-
>>>> address_strings[RPC_DISPLAY_ADDR]);
>>>          }
>>>   +       transport->file = NULL;
>>> +       fput(filp);
>> Please just call xprt_force_disconnect() so that this can be cleaned up
>> from     a safe context.
>
> Hi, Trond
>
> Thank you for your advice, I tried this, but it doesn't seem to
>
> work and an error is reported. I'll analyze why this happens
>
>
Hi, Trond.

If I call xprt_force_disconnect(), it reports the following error,
I spent a long time but couldn't find the cause of the error. If I
call xs_close(), it works, is it possible to call xs_close() here?

[  107.147326][ T7128]
======================================================
[  107.147329][ T7128] WARNING: possible circular locking dependency
detected
[  107.147333][ T7128] 5.17.0+ #10 Not tainted
[  107.147340][ T7128]
------------------------------------------------------
[  107.147343][ T7128] rpc.nfsd/7128 is trying to acquire lock:
[  107.147349][ T7128] ffffffff850f4960 (console_owner){..-.}-{0:0}, at:
console_unlock+0x1d7/0x790
[  107.147384][ T7128]
[  107.147384][ T7128] but task is already holding lock:
[  107.147387][ T7128] ffff88824010b418 (&pool->lock/1){-.-.}-{2:2}, at:
__queue_work+0x450/0x810
[  107.147420][ T7128]
[  107.147420][ T7128] which lock already depends on the new lock.
[  107.147420][ T7128]
[  107.147423][ T7128]
[  107.147423][ T7128] the existing dependency chain (in reverse order) is:
[  107.147426][ T7128]
[  107.147426][ T7128] -> #2 (&pool->lock/1){-.-.}-{2:2}:
[  107.147444][ T7128]        _raw_spin_lock+0x32/0x50
[  107.147482][ T7128]        __queue_work+0x131/0x810
[  107.147496][ T7128]        queue_work_on+0x88/0x90
[  107.147509][ T7128]        tty_flip_buffer_push+0x34/0x40
[  107.147525][ T7128]        serial8250_rx_chars+0x73/0x80
[  107.147537][ T7128] serial8250_handle_irq.part.21+0x124/0x160
[  107.147552][ T7128] serial8250_default_handle_irq+0x79/0x90
[  107.147566][ T7128]        serial8250_interrupt+0x73/0xd0
[  107.147581][ T7128]        __handle_irq_event_percpu+0x54/0x3c0
[  107.147597][ T7128]        handle_irq_event_percpu+0x1c/0x50
[  107.147611][ T7128]        handle_irq_event+0x3e/0x60
[  107.147624][ T7128]        handle_edge_irq+0xc3/0x250
[  107.147636][ T7128]        __common_interrupt+0x71/0x140
[  107.147649][ T7128]        common_interrupt+0xbc/0xe0
[  107.147664][ T7128]        asm_common_interrupt+0x1e/0x40
[  107.147677][ T7128]        default_idle+0x14/0x20
[  107.147687][ T7128]        arch_cpu_idle+0xf/0x20
[  107.147698][ T7128]        default_idle_call+0x6f/0x230
[  107.147709][ T7128]        do_idle+0x1c4/0x250
[  107.147722][ T7128]        cpu_startup_entry+0x1d/0x20
[  107.147736][ T7128]        start_secondary+0xe6/0xf0
[  107.147751][ T7128] secondary_startup_64_no_verify+0xc3/0xcb
[  107.147767][ T7128]
[  107.147767][ T7128] -> #1 (&port_lock_key){-.-.}-{2:2}:
[  107.147783][ T7128]        _raw_spin_lock_irqsave+0x42/0x60
[  107.147795][ T7128]        serial8250_console_write+0x31b/0x380
[  107.147808][ T7128]        univ8250_console_write+0x3a/0x50
[  107.147820][ T7128]        console_unlock+0x51d/0x790
[  107.147832][ T7128]        vprintk_emit+0x252/0x320
[  107.147844][ T7128]        vprintk_default+0x2b/0x30
[  107.147856][ T7128]        vprintk+0x71/0x80
[  107.147868][ T7128]        _printk+0x63/0x82
[  107.147879][ T7128]        register_console+0x233/0x400
[  107.147892][ T7128]        univ8250_console_init+0x35/0x3f
[  107.147907][ T7128]        console_init+0x233/0x345
[  107.147920][ T7128]        start_kernel+0xa70/0xbf8
[  107.147931][ T7128]        x86_64_start_reservations+0x2a/0x2c
[  107.147947][ T7128]        x86_64_start_kernel+0x90/0x95
[  107.147961][ T7128] secondary_startup_64_no_verify+0xc3/0xcb
[  107.147975][ T7128]
[  107.147975][ T7128] -> #0 (console_owner){..-.}-{0:0}:
[  107.147990][ T7128]        __lock_acquire+0x1552/0x1a30
[  107.148002][ T7128]        lock_acquire+0x25e/0x2f0
[  107.148014][ T7128]        console_unlock+0x22e/0x790
[  107.148026][ T7128]        vprintk_emit+0x252/0x320
[  107.148038][ T7128]        vprintk_default+0x2b/0x30
[  107.148050][ T7128]        vprintk+0x71/0x80
[  107.148061][ T7128]        _printk+0x63/0x82
[  107.148072][ T7128]        report_bug+0x1a6/0x1c0
[  107.148085][ T7128]        handle_bug+0x43/0x70
[  107.148098][ T7128]        exc_invalid_op+0x18/0x70
[  107.148111][ T7128]        asm_exc_invalid_op+0x12/0x20
[  107.148123][ T7128]        __queue_work+0x72a/0x810
[  107.148136][ T7128]        queue_work_on+0x88/0x90
[  107.148149][ T7128] xprt_schedule_autoclose_locked+0x7a/0xb0
[  107.148162][ T7128]        xprt_force_disconnect+0x53/0x150
[  107.148173][ T7128]        xs_local_setup_socket+0x2b2/0x480
[  107.148188][ T7128]        xs_setup_local+0x24b/0x280
[  107.148200][ T7128]        xprt_create_transport+0xb0/0x340
[  107.148212][ T7128]        rpc_create+0x104/0x2b0
[  107.148226][ T7128]        rpcb_create_local_unix+0xb2/0x2c0
[  107.148242][ T7128]        rpcb_create_local+0x79/0x90
[  107.148256][ T7128]        svc_bind+0x92/0xd0
[  107.148267][ T7128]        nfsd_create_serv+0x131/0x3a0
[  107.148280][ T7128]        write_ports+0x2d4/0x8d0
[  107.148292][ T7128]        nfsctl_transaction_write+0x70/0xb0
[  107.148305][ T7128]        vfs_write+0x11d/0x4b0
[  107.148319][ T7128]        ksys_write+0xe0/0x130
[  107.148330][ T7128]        __x64_sys_write+0x23/0x30
[  107.148343][ T7128]        do_syscall_64+0x34/0xb0
[  107.148356][ T7128] entry_SYSCALL_64_after_hwframe+0x44/0xae
[  107.148369][ T7128]
[  107.148369][ T7128] other info that might help us debug this:
[  107.148369][ T7128]
[  107.148372][ T7128] Chain exists of:
[  107.148372][ T7128]   console_owner --> &port_lock_key --> &pool->lock/1
[  107.148372][ T7128]
[  107.148392][ T7128]  Possible unsafe locking scenario:
[  107.148392][ T7128]
[  107.148395][ T7128]        CPU0                    CPU1
[  107.148397][ T7128]        ----                    ----
[  107.148399][ T7128]   lock(&pool->lock/1);
[  107.148409][ T7128] lock(&port_lock_key);
[  107.148416][ T7128] lock(&pool->lock/1);
[  107.148426][ T7128]   lock(console_owner);
[  107.148432][ T7128]
[  107.148432][ T7128]  *** DEADLOCK ***
[  107.148432][ T7128]
[  107.148434][ T7128] 7 locks held by rpc.nfsd/7128:
[  107.148442][ T7128]  #0: ffff8882480a4460
(sb_writers#12){.+.+}-{0:0}, at: ksys_write+0xe0/0x130
[  107.148474][ T7128]  #1: ffffffff8526ee88 (nfsd_mutex){+.+.}-{3:3},
at: write_ports+0x41/0x8d0
[  107.148503][ T7128]  #2: ffffffff854cdc88
(rpcb_create_local_mutex){+.+.}-{3:3}, at: rpcb_create_local+0x43/0x90
[  107.148534][ T7128]  #3: ffff888243f14740
(&xprt->transport_lock){+.+.}-{2:2}, at: xprt_force_disconnect+0x4b/0x150
[  107.148562][ T7128]  #4: ffffffff851d7a60
(rcu_read_lock){....}-{1:2}, at: __queue_work+0x5a/0x810
[  107.148592][ T7128]  #5: ffff88824010b418
(&pool->lock/1){-.-.}-{2:2}, at: __queue_work+0x450/0x810
[  107.148625][ T7128]  #6: ffffffff851d4d60 (console_lock){+.+.}-{0:0},
at: vprintk_emit+0x114/0x320
[  107.148653][ T7128]
[  107.148653][ T7128] stack backtrace:
[  107.148656][ T7128] CPU: 3 PID: 7128 Comm: rpc.nfsd Not tainted
5.17.0+ #10
[  107.148670][ T7128] Hardware name: QEMU Standard PC (i440FX + PIIX,
1996), BIOS 1.10.2-1ubuntu1 04/01/2014
[  107.148677][ T7128] Call Trace:
[  107.148680][ T7128]  <TASK>
[  107.148685][ T7128]  dump_stack_lvl+0x6c/0x8b
[  107.148702][ T7128]  dump_stack+0x15/0x17
[  107.148715][ T7128]  print_circular_bug.isra.46+0x261/0x2c0
[  107.148767][ T7128]  check_noncircular+0x105/0x120
[  107.148787][ T7128]  __lock_acquire+0x1552/0x1a30
[  107.148800][ T7128]  ? __lock_acquire+0x1552/0x1a30
[  107.148820][ T7128]  lock_acquire+0x25e/0x2f0
[  107.148833][ T7128]  ? console_unlock+0x1d7/0x790
[  107.148848][ T7128]  ? lock_release+0x204/0x2c0
[  107.148865][ T7128]  console_unlock+0x22e/0x790
[  107.148878][ T7128]  ? console_unlock+0x1d7/0x790
[  107.148900][ T7128]  vprintk_emit+0x252/0x320
[  107.148916][ T7128]  vprintk_default+0x2b/0x30
[  107.148931][ T7128]  vprintk+0x71/0x80
[  107.148945][ T7128]  _printk+0x63/0x82
[  107.148959][ T7128]  ? report_bug+0x19a/0x1c0
[  107.148974][ T7128]  ? __queue_work+0x72a/0x810
[  107.148988][ T7128]  report_bug+0x1a6/0x1c0
[  107.149004][ T7128]  handle_bug+0x43/0x70
[  107.149019][ T7128]  exc_invalid_op+0x18/0x70
[  107.149034][ T7128]  asm_exc_invalid_op+0x12/0x20
[  107.149047][ T7128] RIP: 0010:__queue_work+0x72a/0x810
[  107.149063][ T7128] Code: 48 c7 c7 78 7b b8 84 c6 05 b1 f4 39 04 01
e8 ad 65 05 00 e9 7f fe ff ff e8 33 94 11 00 4c 8b 33 e9 ff f9 ff ff e8
26 94 11 00 <0f> 0b e9 d2 fa ff ff e8 1a 94 11 00 4c 8d 7b 68 41 83 cc
02 e9 aa
[  107.149077][ T7128] RSP: 0018:ffffc900042efa88 EFLAGS: 00010093
[  107.149087][ T7128] RAX: 0000000000000000 RBX: ffff88824013c100 RCX:
0000000000000000
[  107.149096][ T7128] RDX: ffff888111b15140 RSI: ffffffff8119be6a RDI:
ffffffff84c6fd9e
[  107.149104][ T7128] RBP: ffffc900042efac8 R08: 0000000000000001 R09:
0000000000000000
[  107.149112][ T7128] R10: 0000000000000002 R11: 000000000000f2ce R12:
0000000000000000
[  107.149120][ T7128] R13: ffff888243f14668 R14: ffff888237c2d440 R15:
ffff888240ffc000
[  107.149134][ T7128]  ? __queue_work+0x72a/0x810
[  107.149151][ T7128]  ? __queue_work+0x72a/0x810
[  107.149169][ T7128]  queue_work_on+0x88/0x90
[  107.149185][ T7128]  xprt_schedule_autoclose_locked+0x7a/0xb0
[  107.149200][ T7128]  xprt_force_disconnect+0x53/0x150
[  107.149213][ T7128]  xs_local_setup_socket+0x2b2/0x480
[  107.149230][ T7128]  xs_setup_local+0x24b/0x280
[  107.149245][ T7128]  xprt_create_transport+0xb0/0x340
[  107.149259][ T7128]  rpc_create+0x104/0x2b0
[  107.149278][ T7128]  ? __this_cpu_preempt_check+0x1c/0x20
[  107.149293][ T7128]  ? lock_is_held_type+0xde/0x130
[  107.149307][ T7128]  rpcb_create_local_unix+0xb2/0x2c0
[  107.149332][ T7128]  rpcb_create_local+0x79/0x90
[  107.149348][ T7128]  svc_bind+0x92/0xd0
[  107.149363][ T7128]  nfsd_create_serv+0x131/0x3a0
[  107.149378][ T7128]  write_ports+0x2d4/0x8d0
[  107.149392][ T7128]  ? _copy_from_user+0x8b/0xe0
[  107.149411][ T7128]  ? nfsd_init_net+0x2d0/0x2d0
[  107.149425][ T7128]  nfsctl_transaction_write+0x70/0xb0
[  107.149439][ T7128]  ? export_features_show+0x30/0x30
[  107.149454][ T7128]  vfs_write+0x11d/0x4b0
[  107.149470][ T7128]  ksys_write+0xe0/0x130
[  107.149486][ T7128]  __x64_sys_write+0x23/0x30
[  107.149501][ T7128]  do_syscall_64+0x34/0xb0
[  107.149515][ T7128]  entry_SYSCALL_64_after_hwframe+0x44/0xae
[  107.149530][ T7128] RIP: 0033:0x7feb99b00130
[  107.149540][ T7128] Code: 73 01 c3 48 8b 0d 58 ed 2c 00 f7 d8 64 89
01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d b9 45 2d 00 00 75 10 b8 01 00
00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 3e f3 01 00 48
89 04 24
[  107.149553][ T7128] RSP: 002b:00007ffc849b68e8 EFLAGS: 00000246
ORIG_RAX: 0000000000000001
[  107.149565][ T7128] RAX: ffffffffffffffda RBX: 0000000000000000 RCX:
00007feb99b00130
[  107.149574][ T7128] RDX: 0000000000000002 RSI: 000055d532e09620 RDI:
0000000000000003
[  107.149581][ T7128] RBP: 0000000000000003 R08: 000055d532c06704 R09:
0000000000000000
[  107.149589][ T7128] R10: 0000000000000000 R11: 0000000000000246 R12:
0000000000000004
[  107.149597][ T7128] R13: 000055d532e09620 R14: 000055d532c066bf R15:
000055d533474730
[  107.149614][ T7128]  </TASK>
[  107.283659][ T7128] WARNING: CPU: 3 PID: 7128 at
kernel/workqueue.c:1499 __queue_work+0x72a/0x810
[  107.283659][ T7128] Modules linked in:
[  107.283659][ T7128] CPU: 3 PID: 7128 Comm: rpc.nfsd Not tainted
5.17.0+ #10
[  107.283659][ T7128] Hardware name: QEMU Standard PC (i440FX + PIIX,
1996), BIOS 1.10.2-1ubuntu1 04/01/2014
[  107.283659][ T7128] RIP: 0010:__queue_work+0x72a/0x810
[  107.283659][ T7128] Code: 48 c7 c7 78 7b b8 84 c6 05 b1 f4 39 04 01
e8 ad 65 05 00 e9 7f fe ff ff e8 33 94 11 00 4c 8b 33 e9 ff f9 ff ff e8
26 94 11 00 <0f> 0b e9 d2 fa ff ff e8 1a 94 11 00 4c 8d 7b 68 41 83 cc
02 e9 aa
[  107.283659][ T7128] RSP: 0018:ffffc900042efa88 EFLAGS: 00010093
[  107.283659][ T7128] RAX: 0000000000000000 RBX: ffff88824013c100 RCX:
0000000000000000
[  107.283659][ T7128] RDX: ffff888111b15140 RSI: ffffffff8119be6a RDI:
ffffffff84c6fd9e
[  107.283659][ T7128] RBP: ffffc900042efac8 R08: 0000000000000001 R09:
0000000000000000
[  107.283659][ T7128] R10: 0000000000000002 R11: 000000000000f2ce R12:
0000000000000000
[  107.283659][ T7128] R13: ffff888243f14668 R14: ffff888237c2d440 R15:
ffff888240ffc000
[  107.283659][ T7128] FS:  00007feb9a89ac80(0000)
GS:ffff888437c80000(0000) knlGS:0000000000000000
[  107.283659][ T7128] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  107.283659][ T7128] CR2: 00007ffc849ba084 CR3: 0000000247402000 CR4:
00000000000006e0
[  107.283659][ T7128] DR0: 0000000000000000 DR1: 0000000000000000 DR2:
0000000000000000
[  107.283659][ T7128] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7:
0000000000000400
[  107.283659][ T7128] Call Trace:
[  107.283659][ T7128]  <TASK>
[  107.283659][ T7128]  queue_work_on+0x88/0x90
[  107.283659][ T7128]  xprt_schedule_autoclose_locked+0x7a/0xb0
[  107.283659][ T7128]  xprt_force_disconnect+0x53/0x150
[  107.283659][ T7128]  xs_local_setup_socket+0x2b2/0x480
[  107.283659][ T7128]  xs_setup_local+0x24b/0x280
[  107.283659][ T7128]  xprt_create_transport+0xb0/0x340
[  107.283659][ T7128]  rpc_create+0x104/0x2b0
[  107.283659][ T7128]  ? __this_cpu_preempt_check+0x1c/0x20
[  107.283659][ T7128]  ? lock_is_held_type+0xde/0x130
[  107.283659][ T7128]  rpcb_create_local_unix+0xb2/0x2c0
[  107.283659][ T7128]  rpcb_create_local+0x79/0x90
[  107.283659][ T7128]  svc_bind+0x92/0xd0
[  107.283659][ T7128]  nfsd_create_serv+0x131/0x3a0
[  107.283659][ T7128]  write_ports+0x2d4/0x8d0
[  107.283659][ T7128]  ? _copy_from_user+0x8b/0xe0
[  107.283659][ T7128]  ? nfsd_init_net+0x2d0/0x2d0
[  107.283659][ T7128]  nfsctl_transaction_write+0x70/0xb0
[  107.283659][ T7128]  ? export_features_show+0x30/0x30
[  107.283659][ T7128]  vfs_write+0x11d/0x4b0
[  107.283659][ T7128]  ksys_write+0xe0/0x130
[  107.283659][ T7128]  __x64_sys_write+0x23/0x30
[  107.283659][ T7128]  do_syscall_64+0x34/0xb0
[  107.283659][ T7128]  entry_SYSCALL_64_after_hwframe+0x44/0xae
[  107.283659][ T7128] RIP: 0033:0x7feb99b00130
[  107.283659][ T7128] Code: 73 01 c3 48 8b 0d 58 ed 2c 00 f7 d8 64 89
01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d b9 45 2d 00 00 75 10 b8 01 00
00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 3e f3 01 00 48
89 04 24
[  107.283659][ T7128] RSP: 002b:00007ffc849b68e8 EFLAGS: 00000246
ORIG_RAX: 0000000000000001
[  107.283659][ T7128] RAX: ffffffffffffffda RBX: 0000000000000000 RCX:
00007feb99b00130
[  107.283659][ T7128] RDX: 0000000000000002 RSI: 000055d532e09620 RDI:
0000000000000003
[  107.283659][ T7128] RBP: 0000000000000003 R08: 000055d532c06704 R09:
0000000000000000
[  107.283659][ T7128] R10: 0000000000000000 R11: 0000000000000246 R12:
0000000000000004
[  107.283659][ T7128] R13: 000055d532e09620 R14: 000055d532c066bf R15:
000055d533474730
[  107.283659][ T7128]  </TASK>
[  107.283659][ T7128] irq event stamp: 33702
[  107.283659][ T7128] hardirqs last  enabled at (33701):
[<ffffffff814c2288>] cmpxchg_double_slab.isra.52+0xe8/0x220
[  107.283659][ T7128] hardirqs last disabled at (33702):
[<ffffffff8119bfc3>] queue_work_on+0x73/0x90
[  107.283659][ T7128] softirqs last  enabled at (33670):
[<ffffffff8367b7cc>] unix_release_sock+0xfc/0x540
[  107.283659][ T7128] softirqs last disabled at (33668):
[<ffffffff8367b7a8>] unix_release_sock+0xd8/0x540
[  107.283659][ T7128] ---[ end trace 0000000000000000 ]---
[  107.622086][ T7128] svc: failed to register nfsdv2 RPC service (errno
111).
[  107.627373][ T7128] svc: failed to register nfsaclv2 RPC service
(errno 111).
Job for nfs-server.service canceled.
[  109.560632][ T7174] NFSD: Using UMH upcall client tracking operations.
[  109.564229][ T7174] NFSD: starting 90-second grace period (net f0000000)
>>> +
>>>   out:
>>>          xprt_clear_connecting(xprt);
>>>          xprt_wake_pending_tasks(xprt, status);
>
--
Wang Hai