Re: [PATCH v1 0/2] RISC-V: enable rust

From: Trevor Gross
Date: Sat Feb 10 2024 - 03:13:33 EST


On Fri, Feb 9, 2024 at 9:18 AM Conor Dooley <conor@xxxxxxxxxx> wrote:
>
> On Sat, Jan 27, 2024 at 02:46:38PM +0100, Miguel Ojeda wrote:
> > On Fri, Jan 26, 2024 at 11:01 PM Conor Dooley <conor@xxxxxxxxxx> wrote:
> > >
> > > Is that even needed? We already have ARCH_SUPPORTS_CFI_CLANG and AFAIU
> > > rust supports it if clang does, so a second option is superfluous?
> >
> > From a quick look, I don't see it enabled in any RISC-V built-in
> > target in `rustc` yet.
> >
> > It may also still be the case that KCFI needs some tweaks for, say,
> > RISC-V, before the flag actually works, i.e. we couldn't just test the
> > flag in that case -- Ramon: how likely is it that RISC-V would work if
> > KCFI works for aarch64 and x86_64?
>
> Well, there's been no reply here. I'll do sa you suggested and add a
> depends on !CFI_CLANG to RUST.
>
> Cheers,
> Conor.
>

I asked on Zulip and it sounds like Ramon may be out [1]. It
_probably_ works, but going with a dependency to not be blocked on
KCFI is probably reasonable for now.

- Trevor

[1]: https://rust-lang.zulipchat.com/#narrow/stream/343119-project-exploit-mitigations/topic/KCFI.20on.20RISC-V.20questions