Re: [PATCH v5 06/10] x86/asm/efi: Fix asmvalidate warnings for efi_stub_64.S

Matt Fleming
2015-06-11T13:15:01Z

On Wed, 10 Jun, at 07:06:14AM, Josh Poimboeuf wrote:
> Fix the following asmvalidate warnings:
>
> asmvalidate: arch/x86/platform/efi/efi_stub_64.o: efi_call(): missing FP_SAVE/RESTORE macros
> asmvalidate: arch/x86/boot/compressed/efi_stub_64.o: efi_call(): missing FP_SAVE/RESTORE macros
>
> efi_call() is a non-leaf callable function, so save/restore the frame
> pointer with FP_SAVE/RESTORE.
>
> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
> Cc: Matt Fleming <matt.fleming@intel.com>
> Cc: linux-efi@vger.kernel.org
> ---
> arch/x86/platform/efi/efi_stub_64.S | 3 +++
> 1 file changed, 3 insertions(+)

Yeah, fair enough. Though it's worth noting that because we're calling
firmware functions, which use the Microsoft ABI, %rbp will be saved by
the callee function if used. Anyway,

Acked-by: Matt Fleming <matt.fleming@intel.com>

And since I know Boris in particular has poked around in this area, an
ACK from him would be worth alot.

--
Matt Fleming, Intel Open Source Technology Center