> > 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. [1] https://lkml.org/lkml/2013/9/19/235 - Cover letter for EFI runtime services virtual mapping [2] https://lkml.org/lkml/2013/10/8/777 - Talks about efi=old_map [3] https://elixir.bootlin.com/linux/v4.20-rc7/source/arch/x86/platform/efi/efi_64.c#L429 [4] https://elixir.bootlin.com/linux/v4.20-rc7/source/arch/x86/platform/efi/efi.c#L584 > > > Meanwhile, could you please drop these patches before sending pull request > to Linus? > > > > [1] Commit 08cfb38f3ef4 ("x86/efi: Unmap EFI boot services code/data > > regions from efi_pgd") [2] Commit 7e0dabd3010d ("x86/mm/pageattr: > > Introduce helper function to unmap EFI boot services") > > > > I'd like to understand what the issue is before we drop anything. Regards, Sai