Re: [PATCH 08/41] arm64: Replace __ASSEMBLY__ with __ASSEMBLER__ in uapi headers

[Will Deacon]

On Fri, Mar 14, 2025 at 08:09:39AM +0100, Thomas Huth wrote:
> __ASSEMBLY__ is only defined by the Makefile of the kernel, so
> this is not really useful for uapi headers (unless the userspace
> Makefile defines it, too). Let's switch to __ASSEMBLER__ which
> gets set automatically by the compiler when compiling assembly
> code.
> 
> Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
> Cc: Will Deacon <will@xxxxxxxxxx>
> Signed-off-by: Thomas Huth <thuth@xxxxxxxxxx>
> ---
>  arch/arm64/include/uapi/asm/kvm.h        | 2 +-
>  arch/arm64/include/uapi/asm/ptrace.h     | 4 ++--
>  arch/arm64/include/uapi/asm/sigcontext.h | 4 ++--
>  3 files changed, 5 insertions(+), 5 deletions(-)

Is there a risk of breaking userspace with this? I wonder if it would
be more conservative to do something like:

#if !defined(__ASSEMBLY__) && !defined(__ASSEMBLER__)

so that if somebody is doing '#define __ASSEMBLY__' then they get the
same behaviour as today.

Or maybe we don't care?

Will