Re: [PATCH v10 25/27] x86: enable initial Rust support

[Peter Zijlstra]

On Mon, Oct 10, 2022 at 04:15:33PM -0700, Sami Tolvanen wrote:
> On Fri, Oct 7, 2022 at 10:18 AM Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote:
> >
> > On Tue, Sep 27, 2022 at 03:14:56PM +0200, Miguel Ojeda wrote:
> > > Note that only x86_64 is covered and not all features nor mitigations
> > > are handled, but it is enough as a starting point and showcases
> > > the basics needed to add Rust support for a new architecture.
> >
> > Does it fail the build if required options are missing? Specifically are
> > things like kCFI and IBT enabled? Silently not handling those will
> > result in an unbootable image.
> 
> Rust supports IBT with -Z cf-protection=branch, but I don't see this
> option being enabled in the kernel yet. Cross-language CFI is going to
> require a lot more work though because the type systems are not quite
> compatible:

Right; so where does that leave us? Are we going to force disable rust
when kCFI is selected ?