From mboxrd@z Thu Jan 1 00:00:00 1970 From: Keir Fraser Subject: Re: treatment grant frames during save/restore Date: Mon, 31 May 2010 16:29:25 +0100 Message-ID: References: <4C03EAA80200007800004C6A@vpn.id2.novell.com> Mime-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <4C03EAA80200007800004C6A@vpn.id2.novell.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Jan Beulich Cc: "xen-devel@lists.xensource.com" List-Id: xen-devel@lists.xenproject.org On 31/05/2010 15:58, "Jan Beulich" wrote: >> Yep that would probably work. And also potentially gets rid of one lot of >> "if-hvm-else-pv" branched code in xc_domain_save.c. I'd take a patch to do >> that if you want to pick this item up. > > I'm afraid it won't: The live_p2m table gets created for pv guests only, > but is needed as a prerequisite to calling XEN_DOMCTL_getpageframeinfo* > (which wants MFNs as input). Hence while the hypervisor side patch is > trivial, it doesn't get us any closer to a solution to the problem at hand. > > Unless we (re-)define the meaning of the input array to this domctl to > specify gmfn-s rather than mfn-s (at least for the hvm case; for > auto-translate pv guests, quite obviously the save code wouldn't > work anyway, but for those passing in gmfn-s would seem the > natural thing here). This is fine. We can (re-)define the domctl interface as we like, and anyway I'm pretty sure noone uses that particular domctl on HVM guests (yet). -- Keir > Or unless we want to add code to libxc to create a live_p2m for all > guests (which I wouldn't want to take on).