From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:39108) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dwpXV-0003ZF-77 for qemu-devel@nongnu.org; Tue, 26 Sep 2017 09:04:42 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dwpXQ-0006ZX-6R for qemu-devel@nongnu.org; Tue, 26 Sep 2017 09:04:41 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:55184 helo=mx0a-001b2d01.pphosted.com) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dwpXQ-0006Y4-0P for qemu-devel@nongnu.org; Tue, 26 Sep 2017 09:04:36 -0400 Received: from pps.filterd (m0098414.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.21/8.16.0.21) with SMTP id v8QCxOuL098922 for ; Tue, 26 Sep 2017 09:04:30 -0400 Received: from e06smtp10.uk.ibm.com (e06smtp10.uk.ibm.com [195.75.94.106]) by mx0b-001b2d01.pphosted.com with ESMTP id 2d7puvjp5p-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Tue, 26 Sep 2017 09:04:29 -0400 Received: from localhost by e06smtp10.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Tue, 26 Sep 2017 14:04:27 +0100 References: <20170922083855.102341-1-borntraeger@de.ibm.com> <20170922083855.102341-3-borntraeger@de.ibm.com> <5e7ba7d5-82d4-f1e6-532a-37c2c445c227@linux.vnet.ibm.com> <4a31c53b-98aa-747a-1402-1a93e74c565b@de.ibm.com> <5cdfe359-2e78-7e2a-72c2-d3e69574288e@linux.vnet.ibm.com> <20170925120745.7326637e.cohuck@redhat.com> <20da1950-3aa5-c29f-3d54-4f82289f34f1@de.ibm.com> <20170925134532.08e9e273.cohuck@redhat.com> <4cbc3c5b-3050-2e4e-f4cd-0c92fdb8e11f@de.ibm.com> From: Boris Fiuczynski Date: Tue, 26 Sep 2017 15:04:23 +0200 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Message-Id: Content-Transfer-Encoding: quoted-printable Subject: Re: [Qemu-devel] [PATCH/RFC 2/3] s390x/ais: enable ais when migration is available List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Yi Min Zhao , Christian Borntraeger , Cornelia Huck Cc: Halil Pasic , Pierre Morel , David Hildenbrand , qemu-devel , Alexander Graf , "Jason J . Herne" , Richard Henderson On 09/26/2017 11:14 AM, Yi Min Zhao wrote: >=20 >=20 > =E5=9C=A8 2017/9/25 =E4=B8=8B=E5=8D=887:47, Christian Borntraeger =E5=86= =99=E9=81=93: >> On 09/25/2017 01:45 PM, Cornelia Huck wrote: >>> On Mon, 25 Sep 2017 12:12:49 +0200 >>> Christian Borntraeger wrote: >>> >>>> On 09/25/2017 12:07 PM, Cornelia Huck wrote: >>>>> On Fri, 22 Sep 2017 16:27:00 +0200 >>>>> Halil Pasic wrote: >>>>>> One thing I would find very helpful is what do we expect to work=20 >>>>>> and not >>>>>> work for which version. Kind of a matrix. For instance should vfio= =20 >>>>>> pci >>>>>> work for versions prior 2.11. I think in the not so distant past w= e >>>>>> changed how SIC works (so it complains when we don't have ais). >>>>> A matrix sounds like a good idea. >>>> I think we do not even need a matrix, a minimum level will suffice=20 >>>> because... >>>>> I don't think we really ever had a setup that worked out of the box >>>> exactly: ...it never worked until 2.10 and we do not have libvirt=20 >>>> support yet. >>>> Now with the fix 2.10 will also not work, so I think its fair to say >>>> >>>> PCI passthrough via VFIO will be supported for >>>> - KVM: host kernel >=3D 4.13 >>>> - TCG: TBD >>>> - QEMU >=3D 2.11 >>>> - libvirt TBD >>> Make that zpci-per-se, no? >>> >>> with KVM: host kernel >=3D 4.13 && QEMU >=3D 2.11 >>> with TCG: tbd, I don't think anybody has time to wire this up for 2.1= 1 >>> >>> Apropos libvirt: How will it determine whether zpci should be >>> supported? There are some old QEMU + KVM combinations out there that >>> will have a phb (but not be usable by stock Linux guests as the featu= re >>> bits are missing). Version fence? Check for cpu feature support? >> I think for multibus or something like that Boris wanted to check for=20 >> a version >> anyway. So maybe 2.11 (now that 2.10 is broken regarding ais) as a=20 >> minimum QEMU >> level would make sense. >> >> > I think this makes sense. But I think I have to discuss this with Boris. In libvirt multibus is one of the few (very old) supports that would=20 allow checking against a qemu version. Detection of zpci support is another matter since that capability is=20 tied to the existence of the zpci object in qom. Tying the zpci=20 capability to the multibus support has its pro and cons. I have not made=20 up my mind yet. --=20 Mit freundlichen Gr=C3=BC=C3=9Fen/Kind regards Boris Fiuczynski IBM Deutschland Research & Development GmbH Vorsitzender des Aufsichtsrats: Martina K=C3=B6deritz Gesch=C3=A4ftsf=C3=BChrung: Dirk Wittkopp Sitz der Gesellschaft: B=C3=B6blingen Registergericht: Amtsgericht Stuttgart, HRB 243294