Re: [PATCH 3/3] x86: Disable running 32bit processes if ia32_disabled is passed

[Jiri Slaby]

On 08. 06. 23, 8:16, Jiri Slaby wrote:
> On 08. 06. 23, 2:25, Thomas Gleixner wrote:
> > I really wish that we could disable syscall32 reliably on AMD and make
> > it raise #UD as it does on Intal.
>
> Sorry, I am likely missing something, but why is not #GP enough when we 
> set CSTAR = 0?

Or rather to some hole (to avoid mappings when mmap_min_addr=0) or to 
something like entry_SYSCALL32_kill which you suggested elsewhere.

But that is maybe what you consider not being "reliable".

>  It's of course not as good as Intel's *defined* #UD, but 
> why is not the above sufficient/reliable?
>
> thanks,

--
js
suse labs