From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Cooper Subject: Re: [PATCH v3 11/13] x86/altp2m: define and implement alternate p2m HVMOP types. Date: Tue, 7 Jul 2015 21:25:49 +0100 Message-ID: <559C35CD.3010507@citrix.com> References: <1435774177-6345-1-git-send-email-edmund.h.white@intel.com> <1435774177-6345-12-git-send-email-edmund.h.white@intel.com> <559A53D5.5030209@citrix.com> <559B9CEE020000780008D259@mail.emea.novell.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: "Sahita, Ravi" , Jan Beulich , "White, Edmund H" Cc: Wei Liu , George Dunlap , Tim Deegan , Ian Jackson , "xen-devel@lists.xen.org" , "tlengyel@novetta.com" , Daniel De Graaf List-Id: xen-devel@lists.xenproject.org On 07/07/15 21:10, Sahita, Ravi wrote: >> From: Jan Beulich [mailto:JBeulich@suse.com] >> Sent: Tuesday, July 07, 2015 12:34 AM >> >>>>> On 06.07.15 at 12:09, wrote: >>> On 01/07/15 19:09, Ed White wrote: >>>> Signed-off-by: Ed White >>> I am still very much unconvinced by the argument against having a >>> single HVMOP_altp2m and a set of subops. do_domctl() and do_sysctl() >>> are examples of a subop style hypercall with different XSM settings >>> for different subops. >> +1 > > Thanks Andrew and Jan for providing feedback on what the maintainers want to see for the HVMOP_altp2m. > > Just wanted some clarity from a timing perspective on this one so we know how to proceed - is creating a single HVMOP_altp2m and a set of associated subops a requirement to be completed for 4.6 or is that something that can be addressed in a subsequent change? This, unlike most other bits of the series, is an ABI matter. Baring exceptional circumstances, no incompatible changes may be made to the ABI. This, being a guest visible interface, is critical to get right as it cannot be changed at a later point. ~Andrew