Re: [clang] stack protector and f1f029c7bf

[Nick Desaulniers]

On Thu, May 24, 2018 at 1:26 PM Nick Desaulniers <ndesaulniers@xxxxxxxxxx>
wrote:
> On Thu, May 24, 2018 at 11:59 AM <hpa@xxxxxxxxx> wrote:
> > Issue 3: Let's face it, reading and writing the flags should be
builtins,
> exactly because it has to do stack operations, which really means the
> compiler should be involved.

> I'm happy to propose that as a feature request to llvm+gcc.

Oh, looks like both clang and gcc have:
__builtin_ia32_readeflags_u64()

https://godbolt.org/g/SwPjhq

Maybe native_save_fl() and native_restore_fl() should be replaced in the
kernel with
__builtin_ia32_readeflags_u64() and __builtin_ia32_writeeflags_u64()?
-- 
Thanks,
~Nick Desaulniers