[PATCH] efi: arm64: add debugfs node to dump UEFI runtime page tables

[Ard Biesheuvel]

On 30 June 2016 at 16:09, Mark Rutland <mark.rutland at arm.com> wrote:
> On Thu, Jun 30, 2016 at 12:01:46PM +0200, Ard Biesheuvel wrote:
>> Register the debugfs node 'efi_page_tables' to allow the UEFI runtime
>> page tables to be inspected. Note that ARM does not have 'asm/ptdump.h'
>> [yet] so for now, this is arm64 only.
>>
>> Signed-off-by: Ard Biesheuvel <ard.biesheuvel at linaro.org>
>> ---
>>
>> This patch could be helpful in assessing the series 'arm64: avoid block
>> entries that we need to split later' that I sent out yesterday.
>
> It's probably worth noting that this is based on the arm64 for-next/core
> branch. I don't know if/how we can orgnise branches for merging this.
>

There's no rush, so Matt can take it for v4.9 I suppose?

>>  drivers/firmware/efi/arm-runtime.c | 20 ++++++++++++++++++++
>>  1 file changed, 20 insertions(+)
>>
>> diff --git a/drivers/firmware/efi/arm-runtime.c b/drivers/firmware/efi/arm-runtime.c
>> index 17ccf0a8787a..4197a1da013d 100644
>> --- a/drivers/firmware/efi/arm-runtime.c
>> +++ b/drivers/firmware/efi/arm-runtime.c
>> @@ -39,6 +39,26 @@ static struct mm_struct efi_mm = {
>>       .mmlist                 = LIST_HEAD_INIT(efi_mm.mmlist),
>>  };
>>
>> +#ifdef CONFIG_ARM64
>
> If you use CONFIG_ARM64_PTDUMP for the moment, then we won't have some
> unused structs lying around when the feature is unused.
>

I can change that

> Otherwise, I agree that this is a useful debuging feature. FWIW, either
> way:
>
> Acked-by: Mark Rutland <mark.rutland at arm.com>
>

Thanks.