Re: [PATCH v7 38/41] x86/fpu: Add helper for initing features

Edgecombe, Rick P
2023-03-13T23:32:10Z

On Mon, 2023-03-13 at 18:10 +0100, Borislav Petkov wrote:
> > This means that CET_U will always have at least the CET_SHSTK_EN
> > bit
> > set and so not be in the init state. So this can probably just warn
> > and bail if it sees an init state.
>
> I don't mind the additional checks as this is a security thing so
> sanity checks are good, especially if they're cheap.
>
> And you don't need to reinit the buffer - just scream loudly when
> get_xsave_addr()
> returns NULL.

Ok, will do this instead in "x86: Add PTRACE interface for shadow
stack".