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Tsirkin" , Jason Wang Cc: linux-kernel@vger.kernel.org, pasic@linux.ibm.com, borntraeger@de.ibm.com, frankja@linux.ibm.com, cohuck@redhat.com, kvm@vger.kernel.org, linux-s390@vger.kernel.org, virtualization@lists.linux-foundation.org, thomas.lendacky@amd.com, david@gibson.dropbear.id.au, linuxram@us.ibm.com, hca@linux.ibm.com, gor@linux.ibm.com References: <1594801869-13365-1-git-send-email-pmorel@linux.ibm.com> <1594801869-13365-3-git-send-email-pmorel@linux.ibm.com> <20200715054807-mutt-send-email-mst@kernel.org> <20200715074917-mutt-send-email-mst@kernel.org> Message-ID: Date: Thu, 6 Aug 2020 16:19:23 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-TM-AS-GCONF: 00 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.235,18.0.687 definitions=2020-08-06_09:2020-08-06,2020-08-06 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 phishscore=0 suspectscore=0 bulkscore=0 priorityscore=1501 clxscore=1015 lowpriorityscore=0 mlxlogscore=999 malwarescore=0 adultscore=0 mlxscore=0 spamscore=0 impostorscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2006250000 definitions=main-2008060096 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2020-07-30 13:31, Pierre Morel wrote: ...snip... >>>> What bothers me here is that arch code depends on virtio now. >>>> It works even with a modular virtio when functions are inline, >>>> but it seems fragile: e.g. it breaks virtio as an out of tree module, >>>> since layout of struct virtio_device can change. >>> >>> >>> The code was only called from virtio.c so it should be fine. >>> >>> And my understanding is that we don't need to care about the kABI issue >>> during upstream development? >>> >>> Thanks >> >> No, but so far it has been convenient at least for me, for development, >> to just be able to unload all of virtio and load a different version. >> >> >>> >>>> >>>> I'm not sure what to do with this yet, will try to think about it >>>> over the weekend. Thanks! After reflection, I am not sure that this problem must be treated on the architecture level or inside the VIRTIO transport. Consequently, I will propose another patch series based on CCW transport. This also should be more convenient for core development. Regards, Pierre -- Pierre Morel IBM Lab Boeblingen