On 7/12/21 5:33 PM, Kuppuswamy, Sathyanarayanan wrote: > On 7/8/21 5:38 PM, Andi Kleen wrote: >>> Expensive and permanently fractures the direct map. >>> >>> I'm struggling to figure out why the direct map is even touched >>> here. >> I think Sathya did it this way because the TD interface requires a >> physical address. >>> Why not just use a vmalloc area mapping? You really just need >>> *a* decrypted mapping to the page. You don't need to make >>> *every* mapping to the page decrypted. >> >> Yes it would be possible to use vmap() on the page and only set >> the vmap encrypted by passing the right flags directly. > > Is it alright to have non coherent mappings? If yes, any > documentation reference for it? Do you mean non-cache-coherent mappings? I'm not sure what that has to do with creating "unencrypted" (shared) mappings. Are you asking exactly which arguments to pass to vmap() or to vmap_pfn()?
