From mboxrd@z Thu Jan 1 00:00:00 1970 From: =?UTF-8?B?Um9nZXIgUGF1IE1vbm7DqQ==?= Subject: Re: [Draft A] Boot ABI for HVM guests without a device-model Date: Wed, 10 Jun 2015 17:42:21 +0200 Message-ID: <55785ADD.8000200@citrix.com> References: <55782EB8.1060708@citrix.com> <55785480020000780008312B@mail.emea.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 1Z2i9S-0007fk-Ja for xen-devel@lists.xenproject.org; Wed, 10 Jun 2015 15:42:50 +0000 In-Reply-To: <55785480020000780008312B@mail.emea.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 , Ian Campbell , Stefano Stabellini , Andrew Cooper , Tim Deegan , xen-devel , Boris Ostrovsky List-Id: xen-devel@lists.xenproject.org Sorry, forgot to reply to one of your chunks. El 10/06/15 a les 15.15, Jan Beulich ha escrit: >> * cr0: bit 31 (PG) must be cleared. Bit 0 (PE) must be set. Other bits >> are all undefined. > > I see that grub1 documentation says so, but I doubt this is realistic > (even less so for cr4 bits): Some of the bits (including ones not > currently defined) may have a meaning even in non-paged protected > mode, and the environment should be as completely defined as possible. > I.e. I think most other bits should be defined to be zero upon handoff. I think the following is more accurate: * cr0: bit 0 (PE) and bit 4 (ET) will be set. All the other bits are cleared. * cr4: all bits are cleared. Roger.