From: David Woodhouse <dwmw2@xxxxxxxxxxxxx> Date: Wed, 28 Oct 2015 22:57:12 +0900 > On Wed, 2015-10-28 at 07:07 -0700, David Miller wrote: >> In the sparc64 case, the 64-bit DMA address space is divided into >> IOMMU translated and non-IOMMU translated. >> >> You just set the high bits differently depending upon what you want. > > Wait, does that mean a (rogue) device could *always* get full access to > physical memory just by setting the high bits appropriately? That > mapping is *always* available? The IOMMU supports several modes, one of which disallows passthrough and this is what you would use in a virtual guest. -- To unsubscribe from this list: send the line "unsubscribe linux-s390" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
