Hi Nicolas, On Thu, 28 Nov 2024 at 23:58, Nicolas Saenz Julienne <nsaenz@xxxxxxxxxx> wrote: > > Hi Dave, > > On Fri Nov 22, 2024 at 1:03 PM UTC, Dave Young wrote: > > On Wed, 13 Nov 2024 at 02:53, Nicolas Saenz Julienne <nsaenz@xxxxxxxxxx> wrote: > >> > >> Kexec bypasses EFI's switch to virtual mode. In exchange, it has its own > >> routine, kexec_enter_virtual_mode(), which replays the mappings made by > >> the original kernel. Unfortunately, that function fails to reinstate > >> EFI's memory attributes, which would've otherwise been set after > >> entering virtual mode. Remediate this by calling > >> efi_runtime_update_mappings() within kexec's routine. > > > > In the function __map_region(), there are playing with the flags > > similar to the efi_runtime_update_mappings though it looks a little > > different. Is this extra callback really necessary? > > EFI Memory attributes aren't tracked through > `/sys/firmware/efi/runtime-map`, and as such, whatever happens in > `__map_region()` after kexec will not honor them.
