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envelope-from=mjrosato@linux.ibm.com; helo=mx0a-001b2d01.pphosted.com X-Spam_score_int: -26 X-Spam_score: -2.7 X-Spam_bar: -- X-Spam_report: (-2.7 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H5=0.001, RCVD_IN_MSPIKE_WL=0.001, RCVD_IN_VALIDITY_CERTIFIED_BLOCKED=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, SPF_HELO_NONE=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 4/29/25 3:45 AM, Christian Borntraeger wrote: > Am 29.04.25 um 09:37 schrieb David Hildenbrand: > [...] >> The only problem I see is with vfio devices is the new "memory pinned" mode. [1] >> >> There, we'd have to check if any such device is around (discarding of ram is disabled?), and fallback to actual zeroing of memory. > > CC Matt to double check. When triggering the "relaxed translation" mode via iommu.passthrough in the guest, we now take the default (for other platforms) memory_region_is_ram() path in vfio_listener_region_add/del() which handles the pin/unpin from vfio common code. As for ram discarding, we then also use the vfio common path and only uncoordinated discards are disabled via: vfio_ram_block_discard_disable() -> ram_block_uncoordinated_discard_disable() > >> >> [1] https://lkml.kernel.org/r/20250226210013.238349-1-mjrosato@linux.ibm.com >