From mboxrd@z Thu Jan 1 00:00:00 1970 From: Boris Ostrovsky Subject: Re: [PATCH v3 2/4] x86/compat: Test both PV and PVH guests for compat mode Date: Wed, 12 Aug 2015 11:02:18 -0400 Message-ID: <55CB5FFA.3080602@oracle.com> References: <1436566853-8444-1-git-send-email-boris.ostrovsky@oracle.com> <1436566853-8444-3-git-send-email-boris.ostrovsky@oracle.com> <55B111500200007800094A51@prv-mh.provo.novell.com> <55B27BF2.1080902@oracle.com> <55C9DA3802000078000996E8@prv-mh.provo.novell.com> <55CA2F10.6090503@oracle.com> <55CB02780200007800099EE9@prv-mh.provo.novell.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <55CB02780200007800099EE9@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 Cc: elena.ufimtseva@oracle.com, wei.liu2@citrix.com, ian.campbell@citrix.com, stefano.stabellini@eu.citrix.com, andrew.cooper3@citrix.com, ian.jackson@eu.citrix.com, xen-devel@lists.xen.org, roger.pau@citrix.com List-Id: xen-devel@lists.xenproject.org On 08/12/2015 02:23 AM, Jan Beulich wrote: >>>> On 11.08.15 at 19:21, wrote: >> On 08/11/2015 05:19 AM, Jan Beulich wrote: >>>>>> On 24.07.15 at 19:54, wrote: >>>> On 07/23/2015 10:07 AM, Jan Beulich wrote: >>>>> Plus - is this in line with what the tools are doing? Aren't they >>>>> assuming !PV <=> native format context? I.e. don't you need >>>>> to treat differently v->domain == current->domain and its >>>>> opposite? Roger btw. raised a similar question on IRC earlier >>>>> today... >>>> Not sure I understand this. You mean for copying 64-bit guest's info >>>> into 32-bit dom0? >>> Basically yes - tool stack and guest invocations may need to >>> behave differently. >> This being PVH-"classic" it follows exactly the PV path (both in tools >> and the hypervisor). Wouldn't PV be broken then as well? > Note that I raised a question originally (still seen above) instead > of asking for a specific change. In the end all I'm asking for is that > you make changes in the hypervisor in a way compaible with tools > expectations, or adjust the tools accordingly. So the tools have been adjusted (in the 32-bit path) to make PVH behave similarly to PV. This is obviously not what we need to move forward with no-dm PVH but this whole series is really tries to bring 32-bit PVH to parity with (existing) 64-bit PVH. > And of course you > should keep in mind what "no-dm" will want (i.e. perhaps sync with > Roger), such that we don't end up with guest exposed interface > behavior not suitable for the long term targets we have. I suspect the notion of is_pvh_32bit_domain() (which is what this patch adds) will be irrelevant in no-dm world. -boris