On Fri, May 10, 2019 at 06:07:11PM +0000, Dave Hansen wrote: > On 5/8/19 7:43 AM, Kirill A. Shutemov wrote: > > KeyID indicates what key to use to encrypt and decrypt page's content. > > Depending on the implementation a cipher text may be tied to physical > > address of the page. It means that pages with an identical plain text > > would appear different if KSM would look at a cipher text. It effectively > > disables KSM for encrypted pages. > > > > In addition, some implementations may not allow to read cipher text at all. > > > > KSM compares plain text instead (transparently to KSM code). > > > > But we still need to make sure that pages with identical plain text will > > not be merged together if they are encrypted with different keys. > > > > To make it work kernel only allows merging pages with the same KeyID. > > The approach guarantees that the merged page can be read by all users. > > I can't really parse this description. Can I suggest replacement text? Sure. -- Kirill A. Shutemov
