Re: [GIT PULL] x86/urgent for v5.11-rc7

From: Josh Poimboeuf
Date: Sun Feb 07 2021 - 17:47:58 EST


On Sun, Feb 07, 2021 at 10:15:49AM -0800, Linus Torvalds wrote:
> On Sun, Feb 7, 2021 at 9:58 AM Borislav Petkov <bp@xxxxxxx> wrote:
> >
> > It probably is an item on some Intel manager's to-enable list. So far,
> > the CET enablement concentrates only on userspace but dhansen might know
> > more about future plans. CCed.
>
> I think the new Ryzen 5000 series also supports CET, but I don't have
> any machines to check.
>
> Hopefully somebody ends up with hardware that supports it and a urge
> to try to make it work in kernel land too.
>
> I do suspect involved people should start thinking about how they want
> to deal with functions starting with
>
> endbr64
> call __fentry__
>
> instead of the call being at the very top of the function.

FWIW, objtool's already fine with it (otherwise we would have discovered
the need to disable fcf-protection much sooner).

--
Josh