On Mon, 17 Dec 2018 at 19:42, Prakhya, Sai Praneeth <sai.praneeth.prak...@intel.com> wrote: > > > > Hi Thomas and Ingo, > > > > > > I recently noticed that the below commits [1] and [2] are broken when > > > kernel command line argument "efi=old_map" is passed. Sorry! I missed > > > to test this condition prior to sending these patches to mailing list. > > > I am working on a fix and will send it to mailing list as soon as it's > > > ready. > > > > > > > Could you elaborate on the problem please? > > Sure! My bad.. > > Little bit of history here: > Boris with this patch set [1] introduced statically mapping EFI Runtime > Services at -4G > and also introduced "efi=old_map" to return to previous EFI functionality > which used > ioremap and __va(pa). > > [3] and [4] are links to old_map_region() > > The commit 08cfb38f3ef4 ("x86/efi: Unmap EFI boot services code/data regions > from efi_pgd"), > unmaps EFI boot services code/data regions *only* from efi_pgd but > efi=old_map maps > EFI boot services code/data regions into swapper_pgd. Also, efi=old_map uses > either > ioremap() or __va(md->phys_addr) to map EFI runtime/boot time services and > doesn't use kernel_map_pages_in_pgd(). > > So, we need a different unmapping routine to unmap EFI boot services code/data > regions from swapper_pgd if they were mapped using efi=old_map. >
For the short term, could we simply make your changes dependent on efi != old_map? That gives us some time to fix the old_map case properly.