On Thu, Apr 2, 2020 at 11:36 AM Kees Cook <keescook@xxxxxxxxxxxx> wrote: > > Yup, I think it's a weakness of the ARM implementation and I'd like to > not extend it further. AFAIK we should never nest, but I would not be > surprised at all if we did. Wel, at least the user_access_begin/end() sections can't nest. objtool verifies and warns about that on x86. > If we were looking at a design goal for all architectures, I'd like > to be doing what the public PaX patchset We already do better than PaX ever did. Seriously. Mainline has long since passed their hacky garbage. Plus PaX and grsecurity should be actively shunned. Don't look at it, don't use it, and tell everybody you know to not use that shit. Linus