Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932694Ab3CUWyu (ORCPT ); Thu, 21 Mar 2013 18:54:50 -0400 Received: from ozlabs.org ([203.10.76.45]:46458 "EHLO ozlabs.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932358Ab3CUWyt convert rfc822-to-8bit (ORCPT ); Thu, 21 Mar 2013 18:54:49 -0400 From: Michael Neuling To: Chen Gang cc: Benjamin Herrenschmidt , sfr@canb.auug.org.au, "paulus\@samba.org" , matt@ozlabs.org, imunsie@au1.ibm.com, linuxppc-dev@lists.ozlabs.org, "linux-kernel\@vger.kernel.org" Subject: Re: [Suggestion] PowerPC: kernel: cross compiling issue with allmodconfig In-reply-to: <514AA0D9.1090509@asianux.com> References: <51428C81.6000204@asianux.com> <25841.1363323174@ale.ozlabs.ibm.com> <5142AE27.7060003@asianux.com> <514AA0D9.1090509@asianux.com> Comments: In-reply-to Chen Gang message dated "Thu, 21 Mar 2013 13:55:37 +0800." X-Mailer: MH-E 8.2; nmh 1.5; GNU Emacs 23.4.1 MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8BIT Date: Fri, 22 Mar 2013 09:54:46 +1100 Message-ID: <10123.1363906486@ale.ozlabs.ibm.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4309 Lines: 122 Chen Gang wrote: > Hello All: > > summary: > the root cause is no enough room in exception area (0x5500 -- 0x7000). > > it is caused by the patches "for saving/restre PPR": > they consumed much space of this area (0x5500 -- 0x7000). > for pseries_defconfig and ppc64_defconfig, it is still ok. > but for allmodconfig and "some additional config", it will cause issue. > > the solving patch "Make room in exception vector area" can make room larger. > it can let "some additional config" ok. > but for allmodconfig, it is still not enough. > > > details > reason: > it is caused by: > commit number: 13e7a8e846c2ea38a552b986ea49332f965bbb7a > commit number: 44e9309f1f357794b7ae93d5f3e3e6f11d2b8a7f > they are "for saving/restore PPR" > by Haren Myneni Thu, 6 Dec 2012 > compiling result: > pseries_defconfig: pass (cpu for POWER7) > ppc64_defconfig: pass (cpu for POWER7) > allmodconfig: failed (cpu for POWER7) > > analysing: > solving patch: > ------------------------------------------------------------------ > commit number: 61383407677aef05928541a00678591abea2d84c > Author: Benjamin Herrenschmidt > Date: Thu Jan 10 17:44:19 2013 +1100 > > powerpc: Make room in exception vector area > > The FWNMI region is fixed at 0x7000 and the vector are now > overflowing that with some configurations. Fix that by moving > some hash management code out of that region as it doesn't need > to be that close to the call sites (isn't accessed using > conditional branches). > ------------------------------------------------------------------ > > but for allmodconfig (not only for "some configurations"): > it really can reduce much overflow bytes, > (maybe from hundreds bytes to dozens bytes) > but still not enough (still content overflow bytes) > > additional trying: > after del CONFIG_VSX and CONFIG_PPC_970_NAP in allmodconfig, > (will reduce dozens bytes in the region .0x5500 -- .0x7000) > it can pass compiling (not overflow). > > > next: > I am sorry: > I am not quite familiar with the detail features of powerpc. > it seems I am not the suitable member to continue trying. > > I prefer Benjamin to continue trying (just like what he has done). > > if Benjamin will not do it (e.g. maybe no time to do) > I should continue: "make additional room in exception vector area". > (if get no reply within a week: before 2013-03-28, I should continue) > > > > welcome any members' (especially Benjamin) suggestions or completions. This is great, thanks a lot. If you want this to be picked up by the maintainer, you'll need to add your signed-off-by. The signed-off-by is to indicate that your happy for it to be included and that you're legally allowed to do so. See http://gerrit.googlecode.com/svn/documentation/2.0/user-signedoffby.html for more info. Mikey > > thanks. > > :-) > > > On 2013年03月15日 13:14, Chen Gang wrote: > > 于 2013年03月15日 12:52, Michael Neuling 写道: > >> Yep it's a known problem but no one has bothered to fix it since it > >> doesn't happen in a config that anyone cares about like > >> pseries_defconfig and ppc64_defconfig. We've been moving code around in > >> this area a lot recently hence the breakage. > >> > >> It should be fixed though. Patches welcome. :-) > > > > thanks, and I should try, and very glad to try. > > > > :-) :-) > > > > excuse me, I try to provide related patch within this month (2013-03-31), is it ok ? > > the reason is: > > I am not familiar with ppc assembly code, neither ppc kernel, > > so need additional time resource. > > (originally, I worked for x86(_64) core dump analysing for kernel and user programs) > > > > thanks. > > > > > -- > Chen Gang > > Asianux Corporation > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/