Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756883Ab1DMS1K (ORCPT ); Wed, 13 Apr 2011 14:27:10 -0400 Received: from mga11.intel.com ([192.55.52.93]:31059 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751801Ab1DMS1I (ORCPT ); Wed, 13 Apr 2011 14:27:08 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.64,205,1301900400"; d="scan'208";a="909126155" Message-ID: <4DA5EAE4.2060406@linux.intel.com> Date: Wed, 13 Apr 2011 11:26:44 -0700 From: "H. Peter Anvin" Organization: Intel Open Source Technology Center User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.15) Gecko/20110307 Fedora/3.1.9-0.39.b3pre.fc14 Thunderbird/3.1.9 MIME-Version: 1.0 To: stefano.stabellini@eu.citrix.com CC: linux-kernel@vger.kernel.org, xen-devel@lists.xensource.com, konrad.wilk@oracle.com, jeremy@goop.org, yinghai@kernel.org, mingo@elte.hu, "H. Peter Anvin" Subject: Re: [PATCH 2/4] x86,xen: introduce x86_init.mapping.pagetable_reserve References: <1302607192-21355-2-git-send-email-stefano.stabellini@eu.citrix.com> In-Reply-To: <1302607192-21355-2-git-send-email-stefano.stabellini@eu.citrix.com> 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 Content-Length: 957 Lines: 24 On 04/12/2011 04:19 AM, stefano.stabellini@eu.citrix.com wrote: > From: Stefano Stabellini > > Introduce a new x86_init hook called pagetable_reserve that during the > initial memory mapping is used to reserve a range of memory addresses for > kernel pagetable usage. > > On native it just calls memblock_x86_reserve_range while on xen it also > takes care of setting the spare memory previously allocated > for kernel pagetable pages from RO to RW, so that it can be used for > other purposes. > What are the *semantics* of this hook? Hooks are insanely nasty if they are just defined by a particular code flow, as evidenced by the royal mess called paravirt_ops. -hpa -- 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/