Return-Path: Received: from metis.ext.pengutronix.de ([92.198.50.35]:33855 "EHLO metis.ext.pengutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751216Ab1AEPBj (ORCPT ); Wed, 5 Jan 2011 10:01:39 -0500 Message-ID: <4D2487CA.5040501@pengutronix.de> Date: Wed, 05 Jan 2011 16:01:30 +0100 From: Marc Kleine-Budde To: Trond Myklebust CC: =?UTF-8?B?VXdlIEtsZWluZS1Lw7ZuaWc=?= , Russell King - ARM Linux , linux-nfs@vger.kernel.org, Linus Torvalds , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Marc Kleine-Budde Subject: Re: still nfs problems [Was: Linux 2.6.37-rc8] References: <20101230171453.GA5787@pengutronix.de> <1293731992.4919.5.camel@heimdal.trondhjem.org> <20101230191846.GB14221@pengutronix.de> <20110103213850.GC25121@pengutronix.de> <1294100558.25100.8.camel@heimdal.trondhjem.org> <20110105084014.GN25121@pengutronix.de> <20110105110517.GQ25121@pengutronix.de> <20110105112701.GA8638@n2100.arm.linux.org.uk> <20110105134045.GS25121@pengutronix.de> <1294239193.3014.9.camel@heimdal.trondhjem.org> In-Reply-To: <1294239193.3014.9.camel@heimdal.trondhjem.org> Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="------------enig25D519CC34284BF7105FB8D9" Sender: linux-nfs-owner@vger.kernel.org List-ID: MIME-Version: 1.0 --------------enig25D519CC34284BF7105FB8D9 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable On 01/05/2011 03:53 PM, Trond Myklebust wrote: > On Wed, 2011-01-05 at 14:40 +0100, Uwe Kleine-K=C3=B6nig wrote:=20 >> Hi Russell, >> >> On Wed, Jan 05, 2011 at 11:27:01AM +0000, Russell King - ARM Linux wro= te: >>> On Wed, Jan 05, 2011 at 12:05:17PM +0100, Uwe Kleine-K=C3=B6nig wrote= : >>>> Hello Trond, >>>> >>>> On Wed, Jan 05, 2011 at 09:40:14AM +0100, Uwe Kleine-K=C3=B6nig wrot= e: >>>>> On Mon, Jan 03, 2011 at 07:22:38PM -0500, Trond Myklebust wrote: >>>>>> The question is whether this is something happening on the server = or the >>>>>> client. Does an older client kernel boot without any trouble? >>>>> I will set up a boot test with 2.6.37 (for statistics) and 2.6.36 t= o >>>>> compare with. If you don't consider .36 to be old enough let me no= w. >>>>> Once the setup is done it should be easy to test .35 (say), too. >>>>> >>>> Marc (cc'd) saw similar[1] problems with .37, when using .36.2 the >>>> problems didn't occur. This was more reliable to trigger and he was= so >>>> kind to bisect the problem. >>>> >>>> When testing v2.6.36-rc3-51-gafa8ccc init hanged. >>>> (babddc72a9468884ce1a23db3c3d54b0afa299f0 is the first bad commit wi= th >>>> this hang.) Commit 56e4ebf877b6043c289bda32a5a7385b80c17dee makes t= he >>>> "init hangs" problem the "fileid changed on tab" problem. >>>> >>>> I could only reproduce that on armv5 machines (imx27, imx28 and at91= ) >>>> but not on armv6 (imx35). >>> >>> FYI, I've seen the "fileid changed" problem, and it looked like a 32-= bit >>> truncation of the fileid. It occurred several times on successive >>> reboots, so I tried to capture a tcpdump trace off the server (Linux >>> 2.6.23-rc8-ga64314e6 - its ancient because I've had issues with buggy= >>> IDE drivers trying to move it forward.) However, for the last couple= >>> of weeks I've been unable to reproduce it. >>> >>> The client was based on 2.6.37-rc6. >>> >>> The "fileid changed" messages popped up after mounting an export with= >>> 'nolock,intr,rsize=3D4096,soft', and then trying to use bash completi= on >>> and 'ls' in a few subdirectories - and entries were missing from the >>> directory lists without 'ls' reporting any errors (which I think is b= ad >>> behaviour in itself.) >> There was a bug in at least -rc5[1] that was considered already fixed = in >> -rc4[2]. The later announcements didn't mention it anymore.=20 >> >>> I don't know why it's stopped producing the errors, although once it >>> went I never investigated it any further (was far too busy trying to >>> get AMBA DMA support working.) >> It seems it was fixed for most users though. Trond? >=20 > As I said, I can't reproduce it. >=20 > I'm seeing a lot of mention of ARM above. Is anyone seeing this bug on > x86, or does it appear to be architecture-specific? It _seems_ to be ARMv5 specific[1]. Uwe did some tests and figured out that disabling dcache on ARMv5 "fixes" the problem, but CONFIG_CPU_DCACHE_WRITETHROUGH isn't enough. [1] Uwe fails to reproduce it on ARMv6. The ARMv6 has a L2 cache and uses IIRC different instructions to flush the L1 caches. (please correct me, if I'm wrong, ARM guys :) cheers, Marc --=20 Pengutronix e.K. | Marc Kleine-Budde | Industrial Linux Solutions | Phone: +49-231-2826-924 | Vertretung West/Dortmund | Fax: +49-5121-206917-5555 | Amtsgericht Hildesheim, HRA 2686 | http://www.pengutronix.de | --------------enig25D519CC34284BF7105FB8D9 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.10 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iEYEARECAAYFAk0kh84ACgkQjTAFq1RaXHPZYACeIwsQIuLez7XieANUchHvhM3N KxQAn07ibbpviIzvnlidOnf7bUKH7uAB =1+YD -----END PGP SIGNATURE----- --------------enig25D519CC34284BF7105FB8D9--