[PATCH] kcov: fix generic Kconfig dependencies if ARCH_WANTS_NO_INSTR

[Marco Elver]

On Wed, 1 Dec 2021 at 16:26, Marco Elver <elver at google.com> wrote:
[...]
> At the time of 0f1441b44e823, we didn't yet have ARCH_WANTS_NO_INSTR,
> but now we can move the Kconfig dependency checks to the generic KCOV
> option. KCOV will be available if:
>
>         - architecture does not care about noinstr, OR
>         - we have objtool support (like on x86), OR
>         - GCC is 12.0 or newer, OR
>         - Clang is 13.0 or newer.
>
> Signed-off-by: Marco Elver <elver at google.com>

I think this is good to pick up. Even though it has an x86 change in
it, I think kcov changes go through -mm. Andrew, x86 maintainers, any
preference?

With the conclusion from [1], I think we decided it's better to take
this now, given we discovered KCOV already appears broken on arm64
(likely due to noinstr) and e.g. syzbot disables it on arm64.

[1] https://lkml.kernel.org/r/Yae+6clmwHox7CHN@FVFF77S0Q05N

Thanks,
-- Marco