From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andy Chittenden Subject: Re: [PATCH] [Bug 16494] NFS client over TCP hangs due to packet loss Date: Tue, 03 Aug 2010 11:25:30 +0100 Message-ID: <4C57EE9A.7040308@gmail.com> References: <4c57cfe8.887b0e0a.2f79.4772@mx.google.com> <20100803.012144.267950450.davem@davemloft.net> <20100803021110.f0b3877b.akpm@linux-foundation.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: David Miller , kuznet-v/Mj1YrvjDBInbfyfbPRSQ@public.gmane.org, pekkas-UjJjq++bwZ7HOG6cAo2yLw@public.gmane.org, jmorris-gx6/JNMH7DfYtjvyW6yDsg@public.gmane.org, yoshfuji-VfPWfsRibaP+Ru+s062T9g@public.gmane.org, kaber-dcUjhNyLwpNeoWH0uzbU5w@public.gmane.org, eric.dumazet-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, William.Allen.Simpson-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, gilad-f4XOiQkOAtcdH0auuBZGHA@public.gmane.org, ilpo.jarvinen-pxSi+dnQzZMxHbG02/KK1g@public.gmane.org, netdev-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-nfs-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Andrew Morton Return-path: In-Reply-To: <20100803021110.f0b3877b.akpm-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org> Sender: linux-nfs-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: netdev.vger.kernel.org On 2010-08-03 10:11, Andrew Morton wrote: > (cc linux-nfs) > > On Tue, 03 Aug 2010 01:21:44 -0700 (PDT) David Miller wrote: > >> From: "Andy Chittenden" >> Date: Tue, 3 Aug 2010 09:14:31 +0100 >> >>> I don't know whether this patch is the correct fix or not but it enables the >>> NFS client to recover. >>> >>> Kernel version: 2.6.34.1 and 2.6.32. >>> >>> Fixes. It clears down >>> any previous shutdown attempts so that reconnects on a socket that's been >>> shutdown leave the socket in a usable state (otherwise tcp_sendmsg() returns >>> -EPIPE). >> >> If the SunRPC code wants to close a TCP socket then use it again, >> it should disconnect by doing a connect() with sa_family == AF_UNSPEC There is code to do that in the SunRPC code in xs_abort_connection() but that's conditionally called from xs_tcp_reuse_connection(): static void xs_tcp_reuse_connection(struct rpc_xprt *xprt, struct sock_xprt *transport) { unsigned int state = transport->inet->sk_state; if (state == TCP_CLOSE && transport->sock->state == SS_UNCONNECTED) return; if ((1 << state) & (TCPF_ESTABLISHED|TCPF_SYN_SENT)) return; xs_abort_connection(xprt, transport); } That's changed since 2.6.26 where it unconditionally did the connect() with sa_family == AF_UNSPEC. FWIW we cannot reproduce this problem with 2.6.26. -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html