From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ian Campbell Subject: Re: [hybrid] : mmap pfn space... Date: Mon, 16 Apr 2012 15:59:38 +0100 Message-ID: <1334588378.14560.207.camel@zakaz.uk.xensource.com> References: <20120323110144.4b2f1d45@mantra.us.oracle.com> <20120413184705.77b4d316@mantra.us.oracle.com> <4F8C2F1A.6010109@tycho.nsa.gov> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <4F8C2F1A.6010109@tycho.nsa.gov> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Daniel De Graaf Cc: "Xen-devel@lists.xensource.com" , Stefano Stabellini List-Id: xen-devel@lists.xenproject.org On Mon, 2012-04-16 at 15:39 +0100, Daniel De Graaf wrote: > On 04/13/2012 09:47 PM, Mukesh Rathor wrote: > > I was thinking of just dividing my pfn space into say 10 chunks, each > > with 10k pages, so 10 guest creations can happen simultaneously. But, > > then xl is not the only process doing the mapping I found out. xenstored > > also needs to map domU frames. > > With Xen 4.2, xenstored should be using the grant table for its shared > page. Similar changes can be made to xenconsoled so that only the domain > build/migrate processes use map_foreign_range. I have a patch to xenconsoled > without the fallback to map_foreign_range sitting around; I was planning to > post it with proper fallback (which I may do soon, looks simple enough). That sounds like a good thing to have, although I don't think we'd take it for 4.2 at this point so you've got some time. I think the privcmd stuff needs to still assume that domain build is not the only privileged mapper of pages and do proper tracking of what it has mapped where. Various debug utilities etc also use this interface, i.e. xenctx (and gdbsx? I suppose Mukesh would know ;-)) Ian.