On Thu, Jun 30, 2022 at 04:16:09PM +0100, Nikos Nikoleris wrote: ... > So unless UEFI maps all memory as Device-nGnRnE we have to do something. I > will try to find out more about UEFI's page tables. > UEFI will map memory as normal-cacheable. You may find section 2.3.6 of the UEFI spec informative. Thanks, drew