RE: [RESEND PATCH 2/6] x86/traps: add a system interrupt table for system interrupt dispatch

Li, Xin3
2022-11-10T23:01:01Z

> > > > > +#pragma GCC diagnostic push
> > > > > +#pragma GCC diagnostic ignored "-Wcast-function-type"
> > > >
> > > > How does this not break CFI ?
> > >
> > > I wasn't aware of it, will check.
> >
> > CFI needs $(cc-option,-fsanitize=kcfi), which, reported on LWN on Jun,
> > 2002, had not yet landed in the LLVM mainline (I'm using GCC). So
> > looks we are replying on people keeping an eye on it to make sure it's not
> broken?
>
> Well, the entire point of the warning that you are disabling here is to catch
> potential CFI failures at compile time, rather than run time :)

Oh, of course I didn't intend to be opposed to CFI.

>
> Clang also has -Wcast-function-type-strict, which Gustavo and Kees are working
> on getting enabled, so that even more CFI failures can be caught at compile
> time.
>
> https://github.com/ClangBuiltLinux/linux/issues/1724
> https://lore.kernel.org/all/?q=-Wcast-function-type-strict
>
> Cheers,
> Nathan