Re: [PATCH] x86/shstk: Enable shadow stack for x32

From: H.J. Lu
Date: Fri Mar 22 2024 - 13:01:08 EST


On Fri, Mar 22, 2024 at 9:56 AM Dave Hansen <dave.hansen@xxxxxxxxx> wrote:
>
> On 3/22/24 09:52, H.J. Lu wrote:
> > On Fri, Mar 22, 2024 at 9:49 AM Dave Hansen <dave.hansen@xxxxxxxxx> wrote:
> >> On 3/15/24 07:04, H.J. Lu wrote:
> >>> 1. Add shadow stack support to x32 signal.
> >>> 2. Use the 64-bit map_shadow_stack syscall for x32.
> >>> 3. Set up shadow stack for x32.
> >>>
> >>> Tested with shadow stack enabled x32 glibc on Intel Tiger Lake.
> >> I don't think we should wire up code that's never going to get used in
> >> practice. I think I'd want to be sure of the existence of some
> >> specific, real-world, long-term users of this before we add a new ABI
> >> that we need to support forever.
> >>
> >> Are there real users?
> > Were you talking about x32 users or x32 users with shadow stack?
>
> x32 users who both want and will use shadow stacks.

Someone can do a survey among x32 users.

> It's been a long time since I've seen an x32 bug report.

Because it just works?

--
H.J.