Re: [PATCH v2] x86/platform/UV: Fix support for EFI_OLD_MEMMAP after BIOS callback updates

From: Matt Fleming
Date: Thu Oct 20 2016 - 08:27:00 EST


On Wed, 19 Oct, at 08:48:51PM, Alex Thorlton wrote:
> Some time ago, we brought our UV BIOS callback code up to speed with the
> new EFI memory mapping scheme, in commit:
>
> d1be84a232e3 ("x86/uv: Update uv_bios_call() to use efi_call_virt_pointer()")
>
> By leveraging some changes that I made to a few of the EFI runtime
> callback mechanisms, in commit:
>
> 80e75596079f ("efi: Convert efi_call_virt() to efi_call_virt_pointer()")
>
> This got everything running smoothly on UV, with the new EFI mapping
> code. However, this left one, small loose end, in that EFI_OLD_MEMMAP
> (a.k.a. efi=old_map) will no longer work on UV, on kernels that include
> the aforementioned changes.
>
> At the time this was not a major issue (in fact, it still really isn't),
> but there's no reason that EFI_OLD_MEMMAP *shouldn't* work on our
> systems. This commit adds a check into uv_bios_call, to see if we have
> the EFI_OLD_MEMMAP bit set in efi.flags. If it is set, we fall back to
> using our old callback method, which uses efi_call directly on the __va
> of our function pointer.
>
> v2: Invert if-statement and add unlikely() hint.
>
> Signed-off-by: Alex Thorlton <athorlton@xxxxxxx>
> Cc: Mike Travis <travis@xxxxxxx>
> Cc: Russ Anderson <rja@xxxxxxx>
> Cc: Dimitri Sivanich <sivanich@xxxxxxx>
> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
> Cc: Ingo Molnar <mingo@xxxxxxxxxx>
> Cc: "H. Peter Anvin" <hpa@xxxxxxxxx>
> Cc: Matt Fleming <matt@xxxxxxxxxxxxxxxxxxx>
> Cc: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx>
> Cc: x86@xxxxxxxxxx
> ---
> arch/x86/platform/uv/bios_uv.c | 10 +++++++++-
> 1 file changed, 9 insertions(+), 1 deletion(-)

Looks fine to me. Applied to 'next'. Thanks!