[PATCH net] sunrpc: fix UDP memory accounting for v4.4 kernel

[PATCH net] sunrpc: fix UDP memory accounting for v4.4 kernel

[JABLONSKY Jan]

The same warnings reported by Jan Stancek may appear also on 4.4
Based on Paolo Abeni's work.

WARNING: at net/ipv4/af_inet.c:155
CPU: 1 PID: 214 Comm: kworker/1:1H Not tainted 4.4.166 #1
Workqueue: rpciod .xprt_autoclose
task: c0000000366f57c0 ti: c000000034134000 task.ti: c000000034134000
NIP [c000000000662268] .inet_sock_destruct+0x158/0x200

Based on: "[net] sunrpc: fix UDP memory accounting"

Signed-off-by: Jan Jablonsky <jan.jablonsky@thalesgroup.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Cc: Jan Stancek <jstancek@redhat.com>
---
 net/sunrpc/xprtsock.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c
index c9c0976d3bbb..72277cb9785e 100644
--- a/net/sunrpc/xprtsock.c
+++ b/net/sunrpc/xprtsock.c
@@ -1056,7 +1056,7 @@ static void xs_udp_data_receive(struct sock_xprt *transport)
 		if (skb == NULL)
 			break;
 		xs_udp_data_read_skb(&transport->xprt, sk, skb);
-		skb_free_datagram(sk, skb);
+		skb_free_datagram_locked(sk, skb);
 	}
 out:
 	mutex_unlock(&transport->recv_mutex);

Re: [PATCH net] sunrpc: fix UDP memory accounting for v4.4 kernel

[Paolo Abeni]

Hi,

On Tue, 2019-10-15 at 07:21 +0000, JABLONSKY Jan wrote:
> The same warnings reported by Jan Stancek may appear also on 4.4
> Based on Paolo Abeni's work.
> 
> WARNING: at net/ipv4/af_inet.c:155
> CPU: 1 PID: 214 Comm: kworker/1:1H Not tainted 4.4.166 #1
> Workqueue: rpciod .xprt_autoclose
> task: c0000000366f57c0 ti: c000000034134000 task.ti: c000000034134000
> NIP [c000000000662268] .inet_sock_destruct+0x158/0x200
> 
> Based on: "[net] sunrpc: fix UDP memory accounting"

Since your goal here is the inclusion into the 4.4.y stable tree, you
should follow the instructions listed here:

https://www.kernel.org/doc/html/latest/process/stable-kernel-rules.html

elsewhere I guess your patch will not be processed properly. The
relevant commit message is merged into Linus tree since some time and
some minor modifications are needed, so you may likely follow option 3.

Cheers,

Paolo

Re: [PATCH net] sunrpc: fix UDP memory accounting for v4.4 kernel

[JABLONSKY Jan]

On Tue, 2019-10-15 at 11:19 +0200, Paolo Abeni wrote:
> Hi,
> 
> On Tue, 2019-10-15 at 07:21 +0000, JABLONSKY Jan wrote:
> > The same warnings reported by Jan Stancek may appear also on 4.4
> > Based on Paolo Abeni's work.
> > 
> > WARNING: at net/ipv4/af_inet.c:155
> > CPU: 1 PID: 214 Comm: kworker/1:1H Not tainted 4.4.166 #1
> > Workqueue: rpciod .xprt_autoclose
> > task: c0000000366f57c0 ti: c000000034134000 task.ti:
> > c000000034134000
> > NIP [c000000000662268] .inet_sock_destruct+0x158/0x200
> > 
> > Based on: "[net] sunrpc: fix UDP memory accounting"
> 
> Since your goal here is the inclusion into the 4.4.y stable tree, you
> should follow the instructions listed here:
> 
> https://www.kernel.org/doc/html/latest/process/stable-kernel-rules.ht
> ml
> 

Sure,
but unfortunetaly I noticed a41bd25ae67d (with comment Cc: stable@vger.kernel.org # 4.4+)
and since then I haven't seen any additional effort to bring (backport) this patch also for 4.4.
So I want to make it clear, before sending the patch to the 4.4.y stable tree

Thanks for feedback