Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755168AbYHGXJt (ORCPT ); Thu, 7 Aug 2008 19:09:49 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753207AbYHGXJl (ORCPT ); Thu, 7 Aug 2008 19:09:41 -0400 Received: from smtp1.linux-foundation.org ([140.211.169.13]:42301 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752246AbYHGXJk (ORCPT ); Thu, 7 Aug 2008 19:09:40 -0400 Date: Thu, 7 Aug 2008 16:08:22 -0700 (PDT) From: Linus Torvalds To: "H. Peter Anvin" cc: Zachary Amsden , Alok Kataria , Ingo Molnar , the arch/x86 maintainers , LKML Subject: Re: [PATCH]Fix broken VMI in 2.6.27-rc.. In-Reply-To: <489B7DFE.5010402@kernel.org> Message-ID: References: <1218136365.23770.52.camel@alok-dev1> <489B6710.9000604@kernel.org> <1218144438.20178.336.camel@bodhitayantram.eng.vmware.com> <489B6A5C.8030400@kernel.org> <1218145344.20178.347.camel@bodhitayantram.eng.vmware.com> <489B6E83.7000202@kernel.org> <1218146154.20178.352.camel@bodhitayantram.eng.vmware.com> <489B7470.5030408@kernel.org> <489B7DFE.5010402@kernel.org> User-Agent: Alpine 1.10 (LFD 962 2008-03-14) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1105 Lines: 27 On Thu, 7 Aug 2008, H. Peter Anvin wrote: > > Just moving it down by 4 MB doesn't help, since the VMI guys want as much as > 64 MB, which is half the standard vmalloc area and hence too much address > space lost. We can't put it at the bottom of the vmalloc area, since that > boundary is not fixed, either. Yeah, ok. Since this is a 32-bit only issue, 64MB is actually a fair chunk of our already limited virtual space. > The one remaining fixed boundary in the machine is the kernel-userspace > boundary. Hence moving the 1:1 area up by one PDE unit and sticking the > fixmap area in that region. Yeah, ok, but I'd be more nervous about the validation issues there. There might be a lot of code that assumes that TASK_SIZE is the start of the 1:1 area. It does sound like a good approach, it just makes me worry about the test coverage. Linus -- 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/