From mboxrd@z Thu Jan 1 00:00:00 1970 From: Razvan Cojocaru Subject: Re: [PATCH] libxc: Add xc_domain_hvm_get_mtrr_type() call Date: Thu, 20 Dec 2012 15:40:45 +0200 Message-ID: <50D3155D.3010205@gmail.com> References: <50D1A9D1.2020106@gmail.com> <50D1D5BD.8080001@gmail.com> <1355929247.14620.436.camel@zakaz.uk.xensource.com> <50D1DCC5.5050309@citrix.com> <1355932443.14620.448.camel@zakaz.uk.xensource.com> <50D1E723.4070201@citrix.com> <1355933739.14620.456.camel@zakaz.uk.xensource.com> <50D1EB56.40400@gmail.com> <20121219174627.GA67643@ocelot.phlegethon.org> <50D216F7.2050801@gmail.com> <20121220115727.GG80837@ocelot.phlegethon.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20121220115727.GG80837@ocelot.phlegethon.org> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Tim Deegan Cc: Andrew Cooper , Ian Campbell , "xen-devel@lists.xen.org" List-Id: xen-devel@lists.xenproject.org >> Unfortunately, due to the design of components I don't control, my >> application does not have the luxury of waiting for an MSR write event. > > Hmm. In that case I guess you can't cache the MTRR state between > lookups, which may be a performance problem for you. Indeed, however I do need the ability to pull the MTRR type for a given address, via a userspace application, from the hypervisor. I'll play around with the libxc implementation and see what I can come up with, then if it'll all seem to work out I'll send the patch to xen-devel. Thanks, Razvan Cojocaru