From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Cooper Subject: Re: [PATCH RFC 5/4] x86: #PF error code adjustments Date: Wed, 11 Nov 2015 16:30:28 +0000 Message-ID: <56436D24.9040206@citrix.com> References: <5642390402000078000B384D@prv-mh.provo.novell.com> <56430B8602000078000B3A58@prv-mh.provo.novell.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mail6.bemta5.messagelabs.com ([195.245.231.135]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1ZwYI5-00033U-5d for xen-devel@lists.xenproject.org; Wed, 11 Nov 2015 16:30:33 +0000 In-Reply-To: <56430B8602000078000B3A58@prv-mh.provo.novell.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: Jan Beulich , xen-devel Cc: Keir Fraser List-Id: xen-devel@lists.xenproject.org On 11/11/15 08:33, Jan Beulich wrote: > Add a definition for the (for now unused) protection key related error > code bit, moving our own custom ones out of the way. In the course of > checking the uses of the latter I realized that while right now they > can only get set on their own, callers would better not depend on that > property and check just for the bit rather than matching the entire > value. > > Signed-off-by: Jan Beulich For the code presented, Reviewed-by: Andrew Cooper > --- > RFC because I noticed that nothing seems to ever set PFEC_page_paged, > so I wonder whether we really need that flag. It is set in hap_p2m_ga_to_gfn() for frames with types of P2M_PAGING_TYPES Did you miss this, or wish to imply that it is actually dead code? > > It also seems to me that the part of paging_gva_to_gfn() dealing with > the nested case can't be quite right: Neither is there any check after > mode->gva_to_gfn() (namely ignoring INVALID_GFN being returned), nor > does the handling of the two involved error code values seem > reasonable. One of the many reasons why nested HVM can't be expected to > reach "supported" state any time soon, I guess. I concur. Yet another item on the "nested" todo list.