Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933304Ab1DMWWK (ORCPT ); Wed, 13 Apr 2011 18:22:10 -0400 Received: from 8bytes.org ([88.198.83.132]:51129 "EHLO 8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933125Ab1DMWWJ (ORCPT ); Wed, 13 Apr 2011 18:22:09 -0400 Date: Thu, 14 Apr 2011 00:22:07 +0200 From: Joerg Roedel To: "H. Peter Anvin" Cc: Yinghai Lu , Ingo Molnar , Alex Deucher , Linus Torvalds , Linux Kernel Mailing List , dri-devel@lists.freedesktop.org, Thomas Gleixner , Tejun Heo Subject: Re: Linux 2.6.39-rc3 Message-ID: <20110413222207.GB18463@8bytes.org> References: <20110412090207.GE19819@8bytes.org> <20110412184433.GF19819@8bytes.org> <20110413064609.GA18777@elte.hu> <20110413172147.GI19819@8bytes.org> <4DA5F62F.3030504@kernel.org> <20110413193459.GL19819@8bytes.org> <4DA60C30.4060606@kernel.org> <20110413215025.GA18463@8bytes.org> <4DA61D26.8050500@zytor.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4DA61D26.8050500@zytor.com> 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: 1289 Lines: 30 On Wed, Apr 13, 2011 at 03:01:10PM -0700, H. Peter Anvin wrote: > On 04/13/2011 02:50 PM, Joerg Roedel wrote: > > On Wed, Apr 13, 2011 at 01:48:48PM -0700, Yinghai Lu wrote: > >> - addr = memblock_find_in_range(0, 1ULL<<32, aper_size, 512ULL<<20); > >> + addr = memblock_find_in_range(0, 1ULL<<32, aper_size, 512ULL<<21); > > > > Btw, while looking at this code I wondered why the 512M goal is enforced > > by the alignment. Start could be set to 512M instead and the alignment > > can be aper_size as it should. Any reason for such a big alignment? > > > > Joerg > > > > P.S.: The box is still in the office, I will try this debug-patch > > tomorrow. > > The only reason that I can think of is that the aperture itself can be > huge, and perhaps 512 MiB is the biggest such known. Well, that would work as well by just using aper_size as alignment, the aperture needs to be aligned on its size anyway. This code only runs when Linux allocates the aperture itself and if I am mistaken is uses always 64MB when doing this. 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/