From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Alan D. Brunelle" Subject: Re: Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected Date: Fri, 22 Aug 2008 16:17:16 -0400 Message-ID: <48AF1ECC.7000205@hp.com> References: <48A36838.3050309@hp.com> <20080819124602.9e8e69f7.akpm@linux-foundation.org> <48AEDD3D.4060507@hp.com> <20080822092549.ddcb7e79.akpm@linux-foundation.org> <20080822171651.GP10544@machine.or.cz> <20080822105136.a8432875.akpm@linux-foundation.org> <20080822193730.GA1598@atjola.homenet> <48AF17C4.4060606@hp.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: =?ISO-8859-1?Q?Bj=F6rn_Steinbrink?= , Andrew Morton , Petr Baudis , linux-kernel@vger.kernel.org, git@vger.kernel.org To: "Alan D. Brunelle" X-From: linux-kernel-owner+glk-linux-kernel-3=40m.gmane.org-S1758243AbYHVURa@vger.kernel.org Fri Aug 22 22:19:31 2008 Return-path: Envelope-to: glk-linux-kernel-3@gmane.org Received: from vger.kernel.org ([209.132.176.167]) by lo.gmane.org with esmtp (Exim 4.50) id 1KWd5f-0004B4-Mu for glk-linux-kernel-3@gmane.org; Fri, 22 Aug 2008 22:18:36 +0200 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758243AbYHVURa convert rfc822-to-quoted-printable (ORCPT ); Fri, 22 Aug 2008 16:17:30 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754880AbYHVURV (ORCPT ); Fri, 22 Aug 2008 16:17:21 -0400 Received: from g1t0028.austin.hp.com ([15.216.28.35]:27831 "EHLO g1t0028.austin.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753935AbYHVURU (ORCPT ); Fri, 22 Aug 2008 16:17:20 -0400 Received: from g5t0030.atlanta.hp.com (g5t0030.atlanta.hp.com [16.228.8.142]) by g1t0028.austin.hp.com (Postfix) with ESMTP id 621141C1F4; Fri, 22 Aug 2008 20:17:19 +0000 (UTC) Received: from ldl.fc.hp.com (ldl.fc.hp.com [15.11.146.30]) by g5t0030.atlanta.hp.com (Postfix) with ESMTP id 200E62406B; Fri, 22 Aug 2008 20:17:19 +0000 (UTC) Received: from localhost (ldl.fc.hp.com [127.0.0.1]) by ldl.fc.hp.com (Postfix) with ESMTP id CB6EB39C00C; Fri, 22 Aug 2008 14:17:18 -0600 (MDT) X-Virus-Scanned: Debian amavisd-new at ldl.fc.hp.com Received: from ldl.fc.hp.com ([127.0.0.1]) by localhost (ldl.fc.hp.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id DoNmrlCc3yjF; Fri, 22 Aug 2008 14:17:17 -0600 (MDT) Received: from [127.0.0.1] (squirrel.fc.hp.com [15.11.146.57]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by ldl.fc.hp.com (Postfix) with ESMTP id A4F4939C06D; Fri, 22 Aug 2008 14:17:16 -0600 (MDT) User-Agent: Thunderbird 2.0.0.16 (X11/20080724) In-Reply-To: <48AF17C4.4060606@hp.com> X-Brightmail-Tracker: AAAAAQAAAAI= X-Whitelist: TRUE Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Archived-At: Alan D. Brunelle wrote: > Bj=F6rn Steinbrink wrote: >> On 2008.08.22 10:51:36 -0700, Andrew Morton wrote: >>> On Fri, 22 Aug 2008 19:16:51 +0200 Petr Baudis wrot= e: >>>> On Fri, Aug 22, 2008 at 09:25:49AM -0700, Andrew Morton wrote: >>>>> One (probably wrong) approach is to run >>>>> >>>>> gitk 1c89ac55017f982355c7761e1c912c88c941483d >>>>> >>>>> then peer at the output, work out which real commits were in that >>>>> merge. >>>>> >>>>> It looks like the merge ended with >>>>> b1b135c8d619cb2c7045d6ee4e48375882518bb5 and started with >>>>> 40c42076ebd362dc69210cccea101ac80b6d4bd4, so perhaps you can do >>>>> >>>>> git bisect bad b1b135c8d619cb2c7045d6ee4e48375882518bb5 >>>>> git bisect good 40c42076ebd362dc69210cccea101ac80b6d4bd4 >>>> ...I don't quite get this - according to the bisection log, >>>> >>>> # good: [b1b135c8d619cb2c7045d6ee4e48375882518bb5] fix spinlock r= ecursion in hvc_console >>>> >>>> and now you want to mark it as bad? >>> >> Alan provided his bisection log as an attachment to the original bug >> report. >> >>> I assume that Alan's bisection search ended up saying that the merg= e >>> commit (1c89ac55017f982355c7761e1c912c88c941483d) was the first bad >>> commit. >> Yep, and that's totally correct as far as bisect is concerned. The >> parents of that merge commit are: >> 88fa08f67bee1a0c765237bdac106a32872f57d2 >> b1b135c8d619cb2c7045d6ee4e48375882518bb5 >> >> And Alan marked both of them as good. >> >> So, unless Alan made a mistake during his bisection, each of the >> branches is correct, but the merge did not lead to a correct result.= So >> while there were no textual conflicts, there were still incompatible >> changes regarding the code semantics and compatibility was not resto= red >> during the merge. >=20 > It's important to note that even if I did make a mistake during the > bisection process (and I certainly wouldn't discount that), recent > kernels still fail: but when I take out that commit from a recent > kernel, it fails. s/fails/succeeds/ >=20 > I put in Andrew's suggested patch (to help find things), and now I > repeatedly get the problems in the attached log. >=20 > Not being an x86 knowledgeable person, I'm a bit concerned about the = RSP > value?! (I enabled stack overflow checking, but that didn't stop thin= gs.) >=20 > Alan >=20