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[80.230.39.63]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-42b53e7ae88sm35288527f8f.6.2025.11.18.22.31.26 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 18 Nov 2025 22:31:27 -0800 (PST) Date: Wed, 19 Nov 2025 01:31:24 -0500 From: "Michael S. Tsirkin" To: Jason Wang Cc: Peter Xu , eduardo@habkost.net, marcel.apfelbaum@gmail.com, philmd@linaro.org, wangyanan55@huawei.com, zhao1.liu@intel.com, qemu-devel@nongnu.org, farosas@suse.de, jinpu.wang@ionos.com, thuth@redhat.com, berrange@redhat.com Subject: Re: [RFC PATCH] virtio-net: introduce strict peer feature check Message-ID: <20251119012954-mutt-send-email-mst@kernel.org> References: <20251107020149.3223-1-jasowang@redhat.com> <20251113110004-mutt-send-email-mst@kernel.org> <20251113114710-mutt-send-email-mst@kernel.org> <20251113124207-mutt-send-email-mst@kernel.org> <20251116014436-mutt-send-email-mst@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: Received-SPF: pass client-ip=170.10.133.124; envelope-from=mst@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, RCVD_IN_VALIDITY_CERTIFIED_BLOCKED=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On Wed, Nov 19, 2025 at 10:06:16AM +0800, Jason Wang wrote: > On Sun, Nov 16, 2025 at 2:45 PM Michael S. Tsirkin wrote: > > > > On Fri, Nov 14, 2025 at 09:51:00AM +0800, Jason Wang wrote: > > > > So IIUC there will be a cluster, it may contain different groups of hosts, > > > > each group should have similar setups so that VMs can freely migrate > > > > between each other within the same group (but may not easily migratable > > > > across groups?). But I don't think I know well on that part in practise. > > > > > > Towards this, we may need to develop tools somewhere to report TAP > > > capability. Or as replied in another thread, developing software > > > fallback for new features, but it seems a burden. > > > > Or more generally, host capability from QEMU POV. > > Or you mean managment POV actually, for example TAP is usually created > by libvirt. > > Thanks So what you propose is really this: 1- create tap 2- run qemu check that it did not fail 3- if it fails guess what the right set of flags is to make it not fail and switch to that and I am saying qemu should help with 3. > > > > -- > > MST > >