From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dave McCracken Subject: Re: [PROPOSED REMOVAL] PV guest superpage mappings Date: Wed, 20 Jul 2011 11:13:39 -0500 Message-ID: <201107201113.40313.dcm@mccr.org> References: Mime-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Keir Fraser Cc: xen-devel@lists.xensource.com List-Id: xen-devel@lists.xenproject.org On Wednesday, July 20, 2011, Keir Fraser wrote: > The PV superpage mapping feature has been in the hypervisor for a while > now, but I'm not away of any use of this feature by an upstream guest > kernel (e.g., and primarily of interest, pv_ops Linux). Am I mistaken, or > is anyone looking into or interested in this? If the feature is unused we > should remove it from the hypervisor in this development cycle, as it's > untested and is nothing more than a maintenance burden and security risk. > If the feature is only used by vendor patches, the hypervisor-side > implementation belongs in that vendor's patch queues too. I submitted a patch to use this feature to Jeremy for inclusion in the Linux kernel tree back when it first went into the hypervisor. I was under the impression it was in his tree, and would eventually make its way into mainline Linux. I must admit I moved on to other projects and did not follow it carefully. What is the current path for Xen-specific patches to be included in Linux mainline? This feature is important for hugepages to work well in a Xen guest. Dave McCracken Oracle Corp. dave.mccracken@oracle.com