>> Yeah, I was talking about 64-bit only. On 32-bit PAE a PGD maps 1/4 of >> the address space which is totally unworkable for stealing. > > But it is also not necessary. So maybe we could make the 64-bit version of use_temporary_mm() use some reserved address mapping to a reserved PGD in the upper half of address space, and the 32-bit version continue to use "user" addresses. It's unclear to me whether adding complexity here would be worth it to remove the 64-bit STAC/CLAC text patching issues. -Tony
