From mboxrd@z Thu Jan 1 00:00:00 1970 From: Paul Durrant Subject: Re: [PATCH] Remove hardcoded xen-platform device initialization Date: Fri, 14 Jun 2013 13:57:55 +0000 Message-ID: <9AAE0902D5BC7E449B7C8E4E778ABCD0039AE5__8825.33392073146$1371218384$gmane$org@LONPEX01CL01.citrite.net> References: <1371117054-5694-1-git-send-email-paul.durrant@citrix.com> <9AAE0902D5BC7E449B7C8E4E778ABCD0039278@LONPEX01CL01.citrite.net> <51BB2024.5030204@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <51BB2024.5030204@redhat.com> Content-Language: en-US List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Paolo Bonzini Cc: "xen-devel@lists.xen.org" , "qemu-devel@nongnu.org" , Stefano Stabellini List-Id: xen-devel@lists.xenproject.org > -----Original Message----- > From: Paolo Bonzini [mailto:paolo.bonzini@gmail.com] On Behalf Of Paolo > Bonzini > Sent: 14 June 2013 14:53 > To: Paul Durrant > Cc: Stefano Stabellini; qemu-devel@nongnu.org; xen-devel@lists.xen.org > Subject: Re: [PATCH] Remove hardcoded xen-platform device initialization > > Il 14/06/2013 04:50, Paul Durrant ha scritto: > >> > This patch is problematic because we can't know for sure the version of > >> > upstream QEMU that is going to be used with Xen. > >> > If we apply this patch and QEMU 1.5 is going to be used with Xen 4.2, > >> > guests won't be able to use PV drivers. > >> > > > Is there not a compatibility matrix? The hardcoded init. is just blatantly the > wrong thing to be doing and it needs to go. > > > > Could my accompanying toolstack patch not be backported to the next 4.2 > release as mitigation? > > I think Ian is right. You should revert the toolstack patch and not > apply this one for now. Then aim at using "-M pc" in 4.4 (and require > 1.6 or 1.7), so that there is no need for a compatibility matrix. > As I said in another mail on the thread, I don't think we'll ever be able to use -M pc, so I'm planning to create a xenfv-2.0 machine type and leave xenfv with the hardcoded device creation semantic. Then I'll add code to libxl to parse qemu's response to -M help and choose xenfv-2.0 if it exists (and specify the -device argument accordingly). Paul