Re: [PATCH 2/6] arm/efi: Allow invocation of arbitrary runtime services [ver #2]

From: Ard Biesheuvel
Date: Wed Nov 23 2016 - 05:35:21 EST


On 23 November 2016 at 09:34, David Howells <dhowells@xxxxxxxxxx> wrote:
> David Howells <dhowells@xxxxxxxxxx> wrote:
>
>> +#define efi_call_runtime(f, ...) sys_table_arg->runtime->f(__VA_ARGS__)
>
> Turns out it's not that simple - of course. runtime->get_variable is just a
> void pointer. The old arm stub was casting it by virtue of assignment to a
> function pointer variable.
>
> The x86_64 appears to be doing bypassing all the compile-time type checking by
> passing the arguments through an ellipsis and then fixing up the argument list
> in the ->call() function.
>
> What I've changed the ARM and ARM64 things to is:
>
> #define efi_call_runtime(f, ...) ((efi_##f##_t *)sys_table_arg->runtime->f)(__VA_ARGS__)
>

Could we please instead fix the definition of efi_runtime_services_t,
given that we have typedefs already for all its members?