I just caught up on mails and saw you had already mentioned that overlapping writes from the guest look fishy in the "the >1Tb block issue". Cache mode might still be interesting because it affects how guest virtio-blk chooses queue ordering mode. Stefan -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html