Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757626AbZF3Bpf (ORCPT ); Mon, 29 Jun 2009 21:45:35 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752452AbZF3Bp1 (ORCPT ); Mon, 29 Jun 2009 21:45:27 -0400 Received: from terminus.zytor.com ([198.137.202.10]:33223 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751486AbZF3Bp0 (ORCPT ); Mon, 29 Jun 2009 21:45:26 -0400 Message-ID: <4A496DF4.7020203@zytor.com> Date: Mon, 29 Jun 2009 18:44:20 -0700 From: "H. Peter Anvin" User-Agent: Thunderbird 2.0.0.14 (X11/20080501) MIME-Version: 1.0 To: Linus Torvalds CC: Yinghai Lu , Ingo Molnar , Mikael Pettersson , Matthew Wilcox , Grant Grundler , Linux Kernel Mailing List , linux-pci@vger.kernel.org Subject: Re: [BUG 2.6.31-rc1] HIGHMEM64G causes hang in PCI init on 32-bit x86 References: <200906261559.n5QFxJH8027336@pilspetsen.it.uu.se> <19013.29264.623540.275538@pilspetsen.it.uu.se> <4A45A5C1.5080701@zytor.com> <19013.59956.144640.331854@pilspetsen.it.uu.se> <20090629022911.GC20297@lackof.org> <4A484A8A.9020704@zytor.com> <19016.41349.636663.515540@pilspetsen.it.uu.se> <20090629112155.GJ5480@parisc-linux.org> <19016.44061.600652.676183@pilspetsen.it.uu.se> <4A490804.3040609@zytor.com> <4A494478.7020304@kernel.org> <4A494E3C.70304@kernel.org> <4A495C0D.2020807@zytor.com> <4A4966EF.6010809@kernel.org> In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1180 Lines: 35 Linus Torvalds wrote: > ... > end = round_up(start, ram_alignment(start)) - 1; > if (end > MAX_RESOURCE_SIZE) > end = MAX_RESOURCE_SIZE; > if (start > end) > continue; > > Because otherwise we'll just be ignoring resources that cross the resource > size boundary, which sounds wrong. > > We _could_ have a RAM resource that crosses the 4GB boundary, after all. > We could, but the *alignment pad* shouldn't be able to cross a power-of-two boundary ("end" is always an aligned-up version of "start"). > That said, I have to admit that I'm getting tired of these bugs that only > happen when we have a 32-bit resource_size_t. So I can understand the > attraction to just forcing it to 64-bit and forgetting about these > irritating issues. Probably would be worth figuring out just how much it would be. -hpa -- H. Peter Anvin, Intel Open Source Technology Center I work for Intel. I don't speak on their behalf. -- 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/