Re: [PATCH v5 02/10] x86: Compile-time asm code validation

Ingo Molnar
2015-06-11T06:11:05Z

* Josh Poimboeuf <jpoimboe@redhat.com> wrote:

> > I imagine that an automatic CFI annotation adder would walk through functions
> > one instruction at a time and keep track of the frame state. If so, then it
> > could verify that common jump targets had identical state and continue walking
> > through them and annotating. I think this would get this case right, and it
> > might be necessary anyway to handle jumps within functions.
>
> This would definitely add complexity to both asmvalidate and the CFI generator.
> In fact it sounds like it would push the CFI generator out of its current awk
> script territory and more into complex C code territory.

I'd count that as a plus: awk isn't a common skillset while C is, and properly
written it doesn't have to be _that_ complex.

Thanks,

Ingo