From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1766996AbXDSVXI (ORCPT ); Thu, 19 Apr 2007 17:23:08 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1766995AbXDSVXH (ORCPT ); Thu, 19 Apr 2007 17:23:07 -0400 Received: from mx1.redhat.com ([66.187.233.31]:49197 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1766996AbXDSVXG (ORCPT ); Thu, 19 Apr 2007 17:23:06 -0400 Message-ID: <4627DDAD.4070805@redhat.com> Date: Thu, 19 Apr 2007 17:22:53 -0400 From: Chuck Ebbert Organization: Red Hat User-Agent: Thunderbird 1.5.0.10 (X11/20070302) MIME-Version: 1.0 To: "H. Peter Anvin" CC: Andi Kleen , Jeremy Fitzhardinge , Andrew Morton , virtualization@lists.osdl.org, lkml , Zachary Amsden , Chris Wright , "Eric W. Biederman" , Linus Torvalds Subject: Re: [PATCH 10/28] i386: map enough initial memory to create lowmem mappings References: <20070414204154.871250608@goop.org> <200704192250.52633.ak@suse.de> <4627D756.5020405@zytor.com> <200704192304.01053.ak@suse.de> <4627DB0C.2010804@zytor.com> In-Reply-To: <4627DB0C.2010804@zytor.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org H. Peter Anvin wrote: > Andi Kleen wrote: >> On Thursday 19 April 2007 22:55:50 H. Peter Anvin wrote: >>> Andi Kleen wrote: >>>>> Is some version of this going in for 2.6.21, or is it not a real >>>>> problem? >>>> When it's only seen with Xen it's not a real problem right now. >>> It's not just seen only with Xen, though. It will affect all kernels >>> in a particular range of sizes, and we have ordinary kernels covering >>> that range (in fact, Xen hardly affects size in that way.) >> >> Then we would have seen reports surely? > > The critical size window is relatively small, though. The size of the > uncompressed kernel mod 4 MB must be above 3.75 MB or so. If you have > less than 1 GB RAM, the window is even smaller. This is strictly > configuration-dependent, and has nothing to do with Xen. It just so > happened that the first people to detect and diagnose it (as opposed to > just "it doesn't boot") were Xen people. I never saw a description of the symptoms of encountering this bug. Does it just hang, or what?