From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tejun Heo Subject: Re: Linux 2.6.39-rc3 Date: Thu, 14 Apr 2011 13:03:37 +0900 Message-ID: <20110414040337.GC12781@mtj.dyndns.org> References: <20110413172147.GI19819@8bytes.org> <4DA5F62F.3030504@kernel.org> <20110413193459.GL19819@8bytes.org> <4DA60C30.4060606@kernel.org> <4DA6145D.9070703@kernel.org> <4DA655E7.3000904@zytor.com> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Content-Disposition: inline In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org To: Linus Torvalds Cc: "H. Peter Anvin" , Yinghai Lu , Joerg Roedel , Ingo Molnar , Alex Deucher , Linux Kernel Mailing List , "dri-devel@lists.freedesktop.org" , Thomas Gleixner List-Id: dri-devel@lists.freedesktop.org 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. =A0However, even if we *do* revert (and the time is running s= hort on > >> not reverting) I would like to understand this particular one, sim= ply > >> because I think it may very well be a problem that is manifesting = itself > >> in other ways on other systems. >=20 > sorry, fingerfart. Anyway, I agree 100%. >=20 > 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. Thanks. --=20 tejun