[PATCH] [PATCH v2] AARCH64: Add gcc Shadow Call Stack support

[Kees Cook]

On Fri, Feb 25, 2022 at 09:47:19PM +0100, Miguel Ojeda wrote:
> On Fri, Feb 25, 2022 at 4:24 AM Dan Li <ashimida at linux.alibaba.com> wrote:
> >
> > +         - Clang (https://clang.llvm.org/docs/ShadowCallStack.html)
> > +         - GCC (https://gcc.gnu.org/onlinedocs/gcc/Instrumentation-Options.html#Instrumentation-Options)
> 
> Maybe Clang: and GCC: instead of the parenthesis?
> 
> > +#ifdef CONFIG_SHADOW_CALL_STACK
> > +#define __noscs __attribute__((__no_sanitize__("shadow-call-stack")))
> > +#endif
> 
> Since both compilers have it, and I guess the `#ifdef` condition would
> work for both, could this be moved into `compiler_types.h` where the
> empty `__noscs` definition is, and remove the one from
> `compiler-clang.h`?

I thought about that too, but I think it's less simple due to the
__has_feature vs CONFIG differences, etc:
https://lore.kernel.org/lkml/202202251243.1E38256F9@keescook/

But maybe __has_feature doesn't really matter here?

-- 
Kees Cook