Re: [PATCH v9 23/42] Documentation/x86: Add CET shadow stack description

On Wed, 2023-06-21 at 16:05 -0700, H.J. Lu wrote:

quoted

Which makes me think if we did want to make a more compatible
longjmp()
a better the way to do it might be an arch_prctl that emits a token
at
the current SSP. This would be loosening up the security somewhat
(have
to be an opt-in), but less so then enabling WRSS. But it would also
be
way simpler, work for all cases (I think), and be faster (maybe?)
than
INCSSPing through a bunch of stacks.

Since longjmp isn't required to be called after setjmp, leaving a
restore
token doesn't work when longjmp isn't called.

Oh good point. Hmm.