From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753121AbYJ1IEt (ORCPT ); Tue, 28 Oct 2008 04:04:49 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752265AbYJ1IEd (ORCPT ); Tue, 28 Oct 2008 04:04:33 -0400 Received: from gw.goop.org ([64.81.55.164]:48196 "EHLO mail.goop.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752059AbYJ1IEc (ORCPT ); Tue, 28 Oct 2008 04:04:32 -0400 Message-ID: <4906C789.7060408@goop.org> Date: Tue, 28 Oct 2008 19:04:25 +1100 From: Jeremy Fitzhardinge User-Agent: Thunderbird 2.0.0.17 (X11/20081009) MIME-Version: 1.0 To: Nick Piggin CC: Linux Kernel Mailing List , Linux Memory Management List Subject: Re: vm_unmap_aliases and Xen References: <49010D41.1080305@goop.org> <200810281619.10388.nickpiggin@yahoo.com.au> In-Reply-To: <200810281619.10388.nickpiggin@yahoo.com.au> X-Enigmail-Version: 0.95.6 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Nick Piggin wrote: > On Friday 24 October 2008 10:48, Jeremy Fitzhardinge wrote: > >> I've been having a few problems with Xen, I suspect as a result of the >> lazy unmapping in vmalloc.c. >> >> One immediate one is that vm_unmap_aliases() will oops if you call it >> before vmalloc_init() is called, which can happen in the Xen case. RFC >> patch below. >> > > Sure, we could do that. If you add an unlikely, and a __read_mostly, > I'd ack it. Thanks for picking this up. > OK, will respin accordingly. >> But the bigger problem I'm seeing is that despite calling >> vm_unmap_aliases() at the pertinent places, I'm still seeing errors >> resulting from stray aliases. Is it possible that vm_unmap_aliases() >> could be missing some, or not completely synchronous? >> > > It's possible, but of course that would not be by design ;) > > I've had another look over it, and nothing obvious comes to > mind. > I found the problem and fixed it; I was just doing the operations in the wrong order. Thanks, J