On Fri, Aug 24, 2018 at 11:36 AM Nadav Amit <nadav.amit@xxxxxxxxx> wrote: > > > > > Urgh.. weren't the fixmaps per cpu? Bah, I remember looking at this > > during PTI, but I seem to have forgotten everything again. > > [ Changed the title. Sorry for hijacking the thread. ] > > Since: > > native_set_fixmap()->set_pte_vaddr()->pgd_offset_k() The fixmaps should be entirely fixed after bootup to constant mappings, except for the KMAP ones, and they are indexed per-cpu. That's what my mental model is, at least. Can you actually find something that changes the fixmaps after boot (again, ignoring kmap)? Maybe worth adding some debugging to verify that? Linus