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: Wed, 19 Dec 2012 17:10:12 +0200 Message-ID: <50D1D8D4.8030300@gmail.com> References: <1355850255.14620.277.camel@zakaz.uk.xensource.com> <50D0A6B1.30702@gmail.com> <1355912063.14620.286.camel@zakaz.uk.xensource.com> <50D19A2B.2050006@gmail.com> <1355916539.14620.332.camel@zakaz.uk.xensource.com> <50D1A9D1.2020106@gmail.com> <50D1D5BD.8080001@gmail.com> <1355929247.14620.436.camel@zakaz.uk.xensource.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1355929247.14620.436.camel@zakaz.uk.xensource.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Ian Campbell Cc: "Tim (Xen.org)" , "xen-devel@lists.xen.org" List-Id: xen-devel@lists.xenproject.org >> I did manage to take 'enabled' into account with what appears to be >> success, but if I've read the situation correctly, there's not much to >> do about 'overlap', unless we save it in hvm_save_mtrr_msr() like it's >> done with 'enabled'. What do you think? > > It's not an architectural thing so I don't think it belongs in there. > > TBH until someone figures out or explains what overlap actually is I > don't know if it even needs exporting or taking into account in > userspace. Well, get_mtrr_range() is being called by is_var_mtrr_overlapped(), which is the function that sets m->overlapped, which is then used quite a lot in the logic of the get_mtrr_type(), which this patch attempts to bring into userspace via libxc. I would quite happily discount all checks against the overlap boolean argument (and my code seems to work like that), but I suspect whoever wrote get_mtrr_type() had good reason to check for that. Thanks, Razvan Cojocaru