On Thu, May 12, 2022 at 03:36:31PM +0200, Thomas Gleixner wrote: > On Wed, May 11 2022 at 05:27, Kirill A. Shutemov wrote: > > LAM_U48 steals bits above 47-bit for tags and makes it impossible for > > userspace to use full address space on 5-level paging machine. > > > Make these features mutually exclusive: whichever gets enabled first > > blocks the othe one. > > So this patch prevents a mapping above 47bit when LAM48 is enabled, but > I fail to spot how an already existing mapping above 47bit would prevent > LAM48 from being enabled. > > Maybe I'm missing something which makes this magically mutually > exclusive. It is in 09/10. See lam_u48_allowed() -- Kirill A. Shutemov
