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This is working > > even when a device has no translation on its RID (i.e., the RID is IOMMU > > bypassed). > > nit: this description seems not accurate. Intel iommu driver enables ATS > in the probe_device() phase. mind tweak a bit to avoid misleading > message. :) It probably shouldn't do this, it should follow ARM and have it dynamic during domain attach. For security we need ATS disabled for blocking domains at a minimum. Jason