Return-Path: Received: from eu1sys200aog105.obsmtp.com ([207.126.144.119]:39463 "EHLO eu1sys200aog105.obsmtp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754065Ab1BXOLN (ORCPT ); Thu, 24 Feb 2011 09:11:13 -0500 Date: Thu, 24 Feb 2011 19:06:27 +0530 From: Shiraz Hashim To: Chuck Lever Cc: Brian Downing , Deepak SIKRI , Armando VISCONTI , Trond Myklebust , "netdev@vger.kernel.org" , Linux NFS Mailing List , Viresh KUMAR , Peppe CAVALLARO , amitgoel Subject: Re: STMMAC driver: NFS Problem on 2.6.37 Message-ID: <20110224133627.GO920@DLHLAP0379> References: <2D04CF75-CA68-4BDC-99A3-FA1DD6113602@oracle.com> <4D2F4453.4040400@st.com> <4D301DD1.9070104@st.com> <593F2676-CA62-4D77-90AD-41F2FAF13EB6@oracle.com> <4D3EBA54.4020308@st.com> <20110209200129.GA6402@glaurung.lavos.net> <20110209205855.GB6402@glaurung.lavos.net> <5CC01953-376D-46FC-99DA-C282332FA40F@oracle.com> Content-Type: text/plain; charset="us-ascii" In-Reply-To: <5CC01953-376D-46FC-99DA-C282332FA40F@oracle.com> Sender: linux-nfs-owner@vger.kernel.org List-ID: MIME-Version: 1.0 On Thu, Feb 10, 2011 at 05:26:16AM +0800, Chuck Lever wrote: > > On Feb 9, 2011, at 3:58 PM, Brian Downing wrote: > > > On Wed, Feb 09, 2011 at 03:12:22PM -0500, Chuck Lever wrote: > >> Based on your console logs, I see that the working case uses UDP to > >> contact the server's mountd, but the failing case uses TCP. You can > >> try explicitly specifying "proto=udp" to force the use of UDP, to test > >> this theory. > > > > This does indeed make it work again for me, thanks! > > > >> Meanwhile, the patch description explicitly states that the default > >> mount option settings have changed. Does it make sense to change the > >> default behavior of NFSROOT mounts to use UDP again? I don't see > >> another way to make this process more reliable across NIC > >> initialization. If this is considered a regression, we can make a > >> patch for 2.6.38-rc and 2.6.37. > > > > I only use nfsroot for development, so I don't have a terribly strong > > opinion. I would point out though that the default u-boot parameters > > for nfsrooting a lot of boards will no longer work at this point, so if > > it's not patched to work again without specifying nfs options I think > > there should at least be a note in the documentation and possibly a > > "maybe try proto=udp?" console message on failure. > > > > I assume it's not feasable to either wait until the chosen interface's > > link is ready before trying to mount nfsroot, or retrying TCP-based > > connections a little bit more aggressively/at all? > > Our goal is to use the same mount logic for both normal user > space mounts and for NFSROOT (that was the purpose of the patch > series this particular patch comes from). It's > exceptionally difficult to add a special case for retrying TCP > connections here, as that would change the behavior of user > space mounts, which often want to fail quickly, and don't need > to worry about NIC initialization. > > Sounds like the right thing to do is restore the default UDP behavior. I'll cook up a patch. Is there some patch available for this now. There is one more observation (on 2.6.37), when I pass nfsroot=$(ip):$(rootpath),udp , then it works fine. If I pass proto=udp then it doesn't work. Is there any difference between the two methods ? -- regards Shiraz