Re: [PATCH v2 0/3] no_profile fn attr and Kconfig for GCOV+PGO

[Nick Desaulniers]

On Tue, Jun 22, 2021 at 11:17 PM Kees Cook <keescook@xxxxxxxxxxxx> wrote:
>
> On Mon, 21 Jun 2021 16:18:19 -0700, Nick Desaulniers wrote:
> > The kernel has been using noinstr for correctness to politely request
> > that the compiler avoid adding various forms of instrumentation to
> > certain functions.
> >
> > GCOV and PGO can both instrument functions, yet the function attribute
> > to disable such instrumentation (no_profile_instrument_function) was not
> > being used to suppress such implementation. Also, clang only just
> > recently gained support for no_profile_instrument_function. GCC has
> > supported that since 7.1+.
> >
> > [...]
>
> Applied to for-next/clang/features, thanks!
>
> [1/3] compiler_attributes.h: define __no_profile, add to noinstr
>       https://git.kernel.org/kees/c/380d53c45ff2
> [2/3] compiler_attributes.h: cleanups for GCC 4.9+
>       https://git.kernel.org/kees/c/ae4d682dfd33
> [3/3] Kconfig: add ARCH_WANTS_NO_INSTR+CC_HAS_NO_PROFILE_FN_ATTR, depend on for GCOV and PGO
>       https://git.kernel.org/kees/c/51c2ee6d121c
>
> Note that I've tweaked the series slightly to move the PGO Kconfig change into
> the PGO patch.

Ok, LGTM.
-- 
Thanks,
~Nick Desaulniers