From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758794AbZEZVl7 (ORCPT ); Tue, 26 May 2009 17:41:59 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757543AbZEZVlv (ORCPT ); Tue, 26 May 2009 17:41:51 -0400 Received: from casper.infradead.org ([85.118.1.10]:37516 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756346AbZEZVlv (ORCPT ); Tue, 26 May 2009 17:41:51 -0400 Subject: Re: [PATCH] drm: i915: ensure objects are allocated below 4GB on PAE From: Peter Zijlstra To: Eric Anholt Cc: Kyle McMartin , airlied@redhat.com, dri-devel@lists.sf.net, linux-kernel@vger.kernel.org, jbarnes@virtuousgeek.org, stable@kernel.org, hugh.dickins@tiscali.co.uk, linux-mm@kvack.org, shaohua.li@intel.com In-Reply-To: <1243373730.8400.26.camel@gaiman.anholt.net> References: <20090526162717.GC14808@bombadil.infradead.org> <1243365473.23657.32.camel@twins> <1243373730.8400.26.camel@gaiman.anholt.net> Content-Type: text/plain Date: Tue, 26 May 2009 23:41:25 +0200 Message-Id: <1243374085.6600.25.camel@laptop> Mime-Version: 1.0 X-Mailer: Evolution 2.26.1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 2009-05-26 at 14:35 -0700, Eric Anholt wrote: > On Tue, 2009-05-26 at 21:17 +0200, Peter Zijlstra wrote: > > On Tue, 2009-05-26 at 12:27 -0400, Kyle McMartin wrote: > > > From: Kyle McMartin > > > > > > Ensure we allocate GEM objects below 4GB on PAE machines, otherwise > > > misery ensues. This patch is based on a patch found on dri-devel by > > > Shaohua Li, but Keith P. expressed reticence that the changes unfairly > > > penalized other hardware. > > > > > > (The mm/shmem.c hunk is necessary to ensure the DMA32 flag isn't used > > > by the slab allocator via radix_tree_preload, which will hit a > > > WARN_ON.) > > > > Why is this, is the gart not PAE friendly? > > > > Seems to me its a grand way of promoting 64bit hard/soft-ware. > > No, the GART's fine. But the APIs required to make the AGP code > PAE-friendly got deprecated, so the patches to fix the AGP code got > NAKed, and Venkatesh never sent out his patches to undeprecate the APIs > and use them. > > It's been like 6 months now, and it's absurd. I'd like to see this > patch go in so people's graphics can start working again and stop > corrupting system memory. For .30 yes, for .31 we need to resolve that AGP issue, 6 months does seem excessive to get something like that sorted.