Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755297AbXKLPcq (ORCPT ); Mon, 12 Nov 2007 10:32:46 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751672AbXKLPci (ORCPT ); Mon, 12 Nov 2007 10:32:38 -0500 Received: from michael.checkpoint.com ([194.29.32.68]:39561 "EHLO michael.checkpoint.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751407AbXKLPci (ORCPT ); Mon, 12 Nov 2007 10:32:38 -0500 Message-ID: <47387214.2010200@checkpoint.com> Date: Mon, 12 Nov 2007 17:32:36 +0200 From: Yoav Artzi User-Agent: Thunderbird 2.0.0.6 (Windows/20070728) MIME-Version: 1.0 To: Jiri Slaby CC: linux-kernel@vger.kernel.org Subject: Re: PAGE_SIZE on 64bit and 32bit machines References: <473865BE.2070806@checkpoint.com> <47386DC9.4020905@gmail.com> In-Reply-To: <47386DC9.4020905@gmail.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1431 Lines: 46 Well, since the size of the kernel stack is one page, I figured it will grow when switching to 64-bit, because some of the types grow and a similar flow/stack will be bigger in 64-bit in comparison to 32-bit. Keeping the page size at 4kb and so keeping the stack at 4kb is a bit dangerous. Isn't it? I know that using one page for a kernel stack is a optional feature, but: a) It's a good feature b) It's already used by major distros, e.g. Red Hat -------- Original Message -------- Subject: Re: PAGE_SIZE on 64bit and 32bit machines From: Jiri Slaby To: Yoav Artzi Date: Monday, November 12, 2007 5:14:17 PM > On 11/12/2007 03:39 PM, Yoav Artzi wrote: > >> According to my knowledge the PAGE_SIZE on 32bit architectures in 4KB. >> Logically, the PAGE_SIZE on 64bit architectures should be 8KB. That's at >> least the way I understand it. However, looking at the kernel code of >> x86_64, I see the PAGE_SIZE is 4KB. >> > > Yes, it stood unchanged, the only difference is 4-level page tables. > > >> Can anyone explain to me what am I missing here? >> > > What led you to that it must be 8k? > > regards, > - 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/