From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030234AbVHKJJh (ORCPT ); Thu, 11 Aug 2005 05:09:37 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1030236AbVHKJJh (ORCPT ); Thu, 11 Aug 2005 05:09:37 -0400 Received: from smtp203.mail.sc5.yahoo.com ([216.136.129.93]:6541 "HELO smtp203.mail.sc5.yahoo.com") by vger.kernel.org with SMTP id S1030234AbVHKJJg (ORCPT ); Thu, 11 Aug 2005 05:09:36 -0400 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=s1024; d=yahoo.com.au; h=Received:Message-ID:Date:From:User-Agent:X-Accept-Language:MIME-Version:To:CC:Subject:References:In-Reply-To:Content-Type:Content-Transfer-Encoding; b=aAFbjsymoTtNMJOms368O1K0RhXjNDf/9lsGAyezUyO7/PENkJW1GaI26Vw7IaqbIyQ4UkuuqTgDqUGXTkvJFsA93SRiJrxM47hDtfd83P1puoOtsBrQZ7QbOui0kj2hSdE3qApl0LIiSUN2iMtaE7oZf39iASOenVeABe41PIk= ; Message-ID: <42FB15C9.9050406@yahoo.com.au> Date: Thu, 11 Aug 2005 19:09:29 +1000 From: Nick Piggin User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.7.8) Gecko/20050513 Debian/1.7.8-1 X-Accept-Language: en MIME-Version: 1.0 To: Benjamin Herrenschmidt CC: Russell King , "Martin J. Bligh" , ncunningham@cyclades.com, Daniel Phillips , Linux Kernel Mailing List , Linux Memory Management , Hugh Dickins , Linus Torvalds , Andrew Morton , Andrea Arcangeli Subject: Re: [RFC][patch 0/2] mm: remove PageReserved References: <42F57FCA.9040805@yahoo.com.au> <200508090710.00637.phillips@arcor.de> <1123562392.4370.112.camel@localhost> <42F83849.9090107@yahoo.com.au> <20050809080853.A25492@flint.arm.linux.org.uk> <523240000.1123598289@[10.10.2.4]> <20050809204100.B29945@flint.arm.linux.org.uk> <1123666046.30257.226.camel@gaston> In-Reply-To: <1123666046.30257.226.camel@gaston> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Benjamin Herrenschmidt wrote: > On Tue, 2005-08-09 at 20:41 +0100, Russell King wrote: > >>On Tue, Aug 09, 2005 at 07:38:52AM -0700, Martin J. Bligh wrote: >> >>>pfn_valid() doesn't tell you it's RAM or not - it tells you whether you >>>have a backing struct page for that address. Could be an IO mapped device, >>>a small memory hole, whatever. >> >>The only things which have a struct page is RAM. Nothing else does. > > > Well, not anymore :) > Well thanks everyone for the discussion and input. If I have missed answering a question, please just mail me privately to let me know. I guess that despite some architecture implementation differences, everyone will be happy to see PageReserved go from core code. So I will send Andrew the patches. After that, we have a few options to move forward with completely getting rid of the flag from the other funny places it has cropped up. A portable page_is_ram() sounds like the best way to go, as it would not use up a page flag. As far as ioremap goes - I would rather completely disallow it from remapping physical pages and enforce that where possible (eg. with page_is_ram()). However, these issues (page_is_ram, swsusp, ioremap) need not be tackled right now. I will bring them up on the lists some time after the core mm/ is working nicely without PageReserved. Thanks, Nick -- SUSE Labs, Novell Inc. Send instant messages to your online friends http://au.messenger.yahoo.com