Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758191Ab1DNJgP (ORCPT ); Thu, 14 Apr 2011 05:36:15 -0400 Received: from 8bytes.org ([88.198.83.132]:36547 "EHLO 8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757904Ab1DNJgO (ORCPT ); Thu, 14 Apr 2011 05:36:14 -0400 Date: Thu, 14 Apr 2011 11:36:12 +0200 From: Joerg Roedel To: Tejun Heo Cc: Linus Torvalds , "H. Peter Anvin" , Yinghai Lu , Ingo Molnar , Alex Deucher , Linux Kernel Mailing List , "dri-devel@lists.freedesktop.org" , Thomas Gleixner Subject: Re: Linux 2.6.39-rc3 Message-ID: <20110414093612.GE18463@8bytes.org> References: <4DA5F62F.3030504@kernel.org> <20110413193459.GL19819@8bytes.org> <4DA60C30.4060606@kernel.org> <4DA6145D.9070703@kernel.org> <4DA655E7.3000904@zytor.com> <20110414040337.GC12781@mtj.dyndns.org> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20110414040337.GC12781@mtj.dyndns.org> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1623 Lines: 36 On Thu, Apr 14, 2011 at 01:03:37PM +0900, Tejun Heo wrote: > Hello, > > On Wed, Apr 13, 2011 at 07:33:40PM -0700, Linus Torvalds wrote: > > On Wednesday, April 13, 2011, Linus Torvalds > > wrote: > > > On Wednesday, April 13, 2011, H. Peter Anvin wrote: > > >> > > >> Yes. ?However, even if we *do* revert (and the time is running short on > > >> not reverting) I would like to understand this particular one, simply > > >> because I think it may very well be a problem that is manifesting itself > > >> in other ways on other systems. > > > > sorry, fingerfart. Anyway, I agree 100%. > > > > we definitely want to also understand the reason for things not > > working, even if we do revert.. > > There were (and still are) places where memblock callers implemented > ad-hoc top-down allocation by stepping down start limit until > allocation succeeds. Several of them have been removed since top-down > became the default behavior, so simply reverting the commit is likely > to cause subtle issues. Maybe the best approach is introducing > @topdown parameter and use it selectively for pure memory allocations. Wouldn't it be better to provide a seperate memblock allocation function which operates top-down and use this one in the places that need it? This way it wouldn't break code that relies on bottom-up. Joerg -- 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/