On Mon, 17 Feb 2020 at 11:01, Steven Price <steven.price@xxxxxxx> wrote: > > On 16/02/2020 16:25, Ard Biesheuvel wrote: > > On Wed, 18 Dec 2019 at 17:25, Steven Price <steven.price@xxxxxxx> wrote: > >> > >> Now walk_page_range() can walk kernel page tables, we can switch the > >> arm64 ptdump code over to using it, simplifying the code. > >> > >> Reviewed-by: Catalin Marinas <catalin.marinas@xxxxxxx> > >> Signed-off-by: Steven Price <steven.price@xxxxxxx> > > > > I did not realize this at the time, but this patch removes the ability > > to dump the EFI page tables on 32-bit ARM. Was that intentional? > > No that wasn't intentional, but I can't instantly see how this change > affects 32-bit ARM. > > <snip (files in arch/arm64)> > >> diff --git a/drivers/firmware/efi/arm-runtime.c b/drivers/firmware/efi/arm-runtime.c > >> index 899b803842bb..9dda2602c862 100644 > >> --- a/drivers/firmware/efi/arm-runtime.c > >> +++ b/drivers/firmware/efi/arm-runtime.c > >> @@ -27,7 +27,7 @@ > >> > >> extern u64 efi_system_table; > >> > >> -#ifdef CONFIG_ARM64_PTDUMP_DEBUGFS > >> +#if defined(CONFIG_PTDUMP_DEBUGFS) && defined(CONFIG_ARM64) > > The previous define was *ARM64* so should never have been true when > building for arm. The new condition should be equivalent (arm64 && > ptdump enabled). > > Am I missing something? > Not at all, I just got confused. IIRC we did have support for dumping the EFI pages tables on 32-bit ARM at *some* point, but it obviously wasn't your patch that removed it. Apologies for the noise.
