Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757088Ab0AOL31 (ORCPT ); Fri, 15 Jan 2010 06:29:27 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756856Ab0AOL30 (ORCPT ); Fri, 15 Jan 2010 06:29:26 -0500 Received: from mtaout03-winn.ispmail.ntl.com ([81.103.221.49]:12500 "EHLO mtaout03-winn.ispmail.ntl.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754230Ab0AOL3Z (ORCPT ); Fri, 15 Jan 2010 06:29:25 -0500 From: Ian Campbell To: Christian Kujau Cc: Cyrill Gorcunov , Brian Gerst , "H. Peter Anvin" , Jeremy Fitzhardinge , LKML In-Reply-To: References: <4B4405B5.9040205@goop.org> <20100106112133.GA5815@lenovo> <4B4633D3.2070903@zytor.com> <20100108215039.GD4967@lenovo> <73c1f2161001091750y67a852dfk7539021dcc82fa1f@mail.gmail.com> <20100110080940.GB5189@lenovo> <1263128343.2393.45.camel@cthulhu.hellion.org.uk> Content-Type: text/plain; charset="UTF-8" Date: Fri, 15 Jan 2010 11:29:10 +0000 Message-ID: <1263554950.16526.27033.camel@zakaz.uk.xensource.com> Mime-Version: 1.0 X-Mailer: Evolution 2.28.2 Content-Transfer-Encoding: 7bit X-SA-Exim-Connect-IP: 62.200.22.2 X-SA-Exim-Mail-From: ijc@hellion.org.uk Subject: Re: 2.6.33-rc2: Xen/Guest switching to user mode with no user page tables X-SA-Exim-Version: 4.2.1 (built Wed, 25 Jun 2008 17:14:11 +0000) X-SA-Exim-Scanned: Yes (on hopkins.hellion.org.uk) X-Cloudmark-Analysis: v=1.1 cv=1ggfb5FlKZQUfF3vzm9UBYZ2uTfLsbs/8dSljwg5+mE= c=1 sm=0 a=WUDd807v63sA:10 a=L9emPyK8aKtpWj3li3QA:9 a=GjrKZu5u8N1tQdJc0pMpGc_ueloA:4 a=HpAAvcLHHh0Zw7uRqdWCyQ==:117 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 2010-01-15 at 00:36 -0800, Christian Kujau wrote: > On Sun, 10 Jan 2010 at 12:59, Ian Campbell wrote: > > The correct fix is for the Xen backend to declare kernel RPL == 0 for 64 > > bit guests -- the hyervisor already takes care of all the necessary > > squashing to ring 3 transparently (because making the guest worry about > > it would break the very common assumption that you can distinguish user > > from kernel CS by RPL). > > Yes' it's a 64bit guest, I should have mentioned this from the beginning. That's OK, I already knew because only 64 bit guests have a separate user page table. > With the 2 patches from Ian and Cyrill applied, the DomU is now booting > fine again (currently running mainline -git). Excellent. These patches are both now in -tip. They are in the urgent branch so I assume they will be heading to mainline before too long. > Cyrill: with your patch alone (for arch/x86/kernel/process.c), the DomU > is still not booting, Dom0 "xm dmesg" reporting the same error. As it's > working with both patches applied, should I try to test with only Ian's > patch (for arch/x86/xen/enlighten.c) applied? It's OK, both patches are definitely required to fix 64 bit guests so there is no point in testing just one or the other. Ian. -- Ian Campbell Current Noise: Exodus - Scar Spangled Banner War is much too serious a matter to be entrusted to the military. -- Clemenceau -- 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/