From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751648Ab1A0P2X (ORCPT ); Thu, 27 Jan 2011 10:28:23 -0500 Received: from adelie.canonical.com ([91.189.90.139]:33695 "EHLO adelie.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751012Ab1A0P2W (ORCPT ); Thu, 27 Jan 2011 10:28:22 -0500 Message-ID: <4D418F0E.6010503@canonical.com> Date: Thu, 27 Jan 2011 16:28:14 +0100 From: Stefan Bader User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.2.13) Gecko/20101208 Lightning/1.0b2 Thunderbird/3.1.7 MIME-Version: 1.0 To: Daniel Kiper CC: linux-kernel@vger.kernel.org, stable@kernel.org, x86@kernel.org, xen-devel@lists.xensource.com, jeremy@goop.org, konrad.wilk@oracle.com, mingo@redhat.com, mingo@elte.hu Subject: Re: [PATCH] xen: convert p2m to a 3 level tree - partial revert References: <20110127144843.GA23746@router-fw-old.local.net-space.pl> <4D41883A.3020603@canonical.com> <4D418907.2030708@canonical.com> <20110127151921.GB23746@router-fw-old.local.net-space.pl> In-Reply-To: <20110127151921.GB23746@router-fw-old.local.net-space.pl> X-Enigmail-Version: 1.1.2 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 01/27/2011 04:19 PM, Daniel Kiper wrote: > Hi, > > On Thu, Jan 27, 2011 at 04:02:31PM +0100, Stefan Bader wrote: >> On 01/27/2011 03:59 PM, Stefan Bader wrote: >>> On 01/27/2011 03:48 PM, Daniel Kiper wrote: >>>> Hi, >>>> >>>> Durning work on Xen memory hotplug I discoverd that >>>> 2.6.38-rc2 does not boot on domU. After some investigation >>>> it appeared that 58e05027b530ff081ecea68e38de8d59db8f87e0 >>>> commit changed CONFIG_XEN_MAX_DOMAIN_MEMORY constant value >>>> to 128. This change does not allow to boot kernel on domU >>>> with small memory size (I could confirm that it is even >>>> not possible to boot kernel on domU with 2 GiB). Guest >>>> crash silently without any warning. Durning further >>>> research I found out that there is another commit published >>>> recently (8e1b4cf2108488ccfb9a3e7ed7cd85a435e01d4b) which attempts >>>> to fix this issue, however, it does not work on my platform. >>>> I decided to reenable CONFIG_XEN_MAX_DOMAIN_MEMORY option in >>>> kernel config and enable users to choose resonable values for >>>> their machines until better fix will be published. I think this >>>> solution is good because allow users to boot domU with newest >>>> kernel and allow developers to continue their work without >>>> time presure which could lead to new bugs. >>> >>> Have you tried with a version that contains >>> >>> commit 8e1b4cf2108488ccfb9a3e7ed7cd85a435e01d4b >>> Author: Stefan Bader >>> Date: Thu Jan 20 15:38:23 2011 +0100 >>> >>> xen: p2m: correctly initialize partial p2m leaf >>> >>> I still may need to send a follow up to add a matching RESERVE_BRK, but at least >>> I was able to boot small DomU's again. >>> >>> -Stefan >>>> This patch applies cleanly to current Linus' kernel tree. >> >> Sorry, did not read careful enough. So you did. Maybe you could actually try to >> make the additional change of >> >> --- a/arch/x86/xen/p2m.c >> +++ b/arch/x86/xen/p2m.c >> @@ -61,6 +61,7 @@ static RESERVE_BRK_ARRAY(unsigned long *, p2m_top_mfn_p, P2M_T >> >> RESERVE_BRK(p2m_mid, PAGE_SIZE * (MAX_DOMAIN_PAGES / (P2M_PER_PAGE * P2M_MID_PE >> RESERVE_BRK(p2m_mid_mfn, PAGE_SIZE * (MAX_DOMAIN_PAGES / (P2M_PER_PAGE * P2M_MI >> +RESERVE_BRK(p2m_node, PAGE_SIZE); >> >> static inline unsigned p2m_top_index(unsigned long pfn) >> { >> >> This one I missed and probably that has more effects on big memory values. > > No, it does not work (CONFIG_XEN_MAX_DOMAIN_MEMORY=128). > Ok, thanks. So out of interest, what size of guest memory is failing for you? -Stefan > Daniel > -- > 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/