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envelope-from=jgg@nvidia.com; helo=BN8PR05CU002.outbound.protection.outlook.com X-Spam_score_int: -14 X-Spam_score: -1.5 X-Spam_bar: - X-Spam_report: (-1.5 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.445, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, FORGED_SPF_HELO=1, SPF_HELO_PASS=-0.001, SPF_NONE=0.001 autolearn=no autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-arm@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-arm-bounces+qemu-arm=archiver.kernel.org@nongnu.org Sender: qemu-arm-bounces+qemu-arm=archiver.kernel.org@nongnu.org On Mon, May 11, 2026 at 08:38:44PM +0200, Mohamed Mediouni wrote: > And not very relevant to Grace + GPU systems specifically, but any hopes of live > migration support are lost outside of very awkward placement trickery when using > this to match host addresses. I think live migration is still possible, it does further limit migration pairs to ones with identical physical topology though. > Is this specific to the NIC attached directly to the GPU (that is > then attached over C2C) configuration? Something like that, it is convoluted. > Using PCIe passthrough with ATS disabled doesn’t sound like such a great idea > on the security side of things imo. The platform was specifically designed in a way that this is secure. Yes it is not a great idea in general but with careful choices it can be made safe. Jason