Re: [PATCH v28 04/10] x86/cet/ibt: Disable IBT for ia32

[Yu, Yu-cheng]

On 8/9/2021 4:04 PM, Andy Lutomirski wrote:
> On 7/22/21 1:57 PM, Yu-cheng Yu wrote:
> > In a signal, a task's IBT status needs to be saved to the signal frame, and
> > later restored in sigreturn.  For the purpose, previous versions of the
> > series add a new struct to the signal frame.  However, a new signal frame
> > format (or re-using a reserved space) introduces complex compatibility
> > issues.
> >
> > In the discussion (see link below), Andy Lutomirski proposed using a
> > ucontext flag.  The approach is clean and eliminates most compatibility
> > issues.
> >
> > However, a legacy IA32 signal frame does not have ucontext and cannot
> > support a uc flag.  Thus,
> >
> > - Disable IBT for ia32.
> > - In ia32 sigreturn, verify ibt is disabled.
>
> Acked-by: Andy Lutomirski <luto@xxxxxxxxxx>

Thanks!