On Tue, Apr 10, 2018 at 09:33:39AM +0000, Kirill A. Shutemov wrote: > AMD SME claims one bit from physical address to indicate whether the > page is encrypted or not. To achieve that we clear out the bit from > __PHYSICAL_MASK. > > The capability to adjust __PHYSICAL_MASK is required beyond AMD SME. > For instance for upcoming Intel Multi-Key Total Memory Encryption. > > Factor it out into a separate feature with own Kconfig handle. > > It also helps with overhead of AMD SME. It saves more than 3k in .text > on defconfig + AMD_MEM_ENCRYPT: > > add/remove: 3/2 grow/shrink: 5/110 up/down: 189/-3753 (-3564) > > We would need to return to this once we have infrastructure to patch > constants in code. That's good candidate for it. > > Signed-off-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx> > Reviewed-by: Tom Lendacky <thomas.lendacky@xxxxxxx> > --- > > Previously, I've posted the patch with MKTME patchset, but it's useful on > its own as it reduces text size for kernel with AMD_MEM_ENCRYPT enabled. > > Please consider applying. Any feedback on this? -- Kirill A. Shutemov
