From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760865AbYETGdS (ORCPT ); Tue, 20 May 2008 02:33:18 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755256AbYETGdI (ORCPT ); Tue, 20 May 2008 02:33:08 -0400 Received: from gw.goop.org ([64.81.55.164]:40338 "EHLO mail.goop.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754996AbYETGdF (ORCPT ); Tue, 20 May 2008 02:33:05 -0400 Message-ID: <48327E92.4060201@goop.org> Date: Tue, 20 May 2008 08:32:34 +0100 From: Jeremy Fitzhardinge User-Agent: Thunderbird 2.0.0.14 (X11/20080501) MIME-Version: 1.0 To: Hugh Dickins CC: Linus Torvalds , Theodore Tso , Gabriel C , Keith Packard , "Pallipadi, Venkatesh" , Eric Anholt , linux-kernel@vger.kernel.org, Ingo Molnar , "Siddha, Suresh B" , bugme-daemon@bugzilla.kernel.org, airlied@linux.ie, "Barnes, Jesse" , Andrew Morton , "Rafael J. Wysocki" Subject: Re: [Bug 10732] REGRESSION: 2.6.26-rc2-git4: X server failed start onX61s laptop References: <924EFEDD5F540B4284297C4DC59F3DEE01119AFE@orsmsx423.amr.corp.intel.com> <20080517154131.GA7651@mit.edu> <924EFEDD5F540B4284297C4DC59F3DEE01119B07@orsmsx423.amr.corp.intel.com> <1211047916.27447.314.camel@koto.keithp.com> <482F24C6.2050705@frugalware.org> <20080517184626.GA16496@mit.edu> In-Reply-To: X-Enigmail-Version: 0.95.6 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hugh Dickins wrote: >> And can we agree to never EVER use that PAGE_MASK thing (which was only >> ever meant to work on *addresses*) for any pte operations (including the >> definition of PTE_MASK)? Because PAGE_MASK is very much the word-size, and >> in 32-bit PAE, the page table entry is bigger. >> >> IOE, PTE_MASK should be a "pteval_t". And it should have absolutely >> *nothing* to do with PAGE_MASK. EVER. >> > > Yes, Jeremy makes it a pteval_t. (My builds and Ingo's builds succeed, > but I've not worked out how that goes down in assembly: there was an > _AT macro in there before, which you've kept too - Jeremy?) > I got rid of a bunch of _AT() uses because the constants aren't used in .S files anywhere. Also, I couldn't see how to represent a 64-bit constant in assembler, so I wasn't sure of their correctness (the as manual is irritatingly vague on the matter). > Yes, I'm highly resistant to taking untested patches here. The two-liner > I sent last night was about my fifth attempt to get it working, and I did > start off from a small PTE_MASK correction which didn't work at all. It > looked rather like yours, I guess I missed the __PHYSICAL_LOW_BITS part. > Jeremy's goes a lot further, he'll know the gotchas better. > __PHYSICAL_LOW_BITS is a bit more elegant than what I did there (the problem is getting a physaddr_t-width PAGE_MASK). But the formulation in my patch certainly works. J