On Mon, Feb 20, 2023 at 10:56:38AM -0800, KP Singh wrote:
> Sure, it looks like an omission to me, we wrote a POC on Skylake that
> was able to do cross-thread training with the current set of
> mitigations.
Right.
> STIBP with IBRS is still correct if spectre_v2=ibrs had really meant
> IBRS everywhere,
Yeah, IBRS everywhere got shot down as a no-no very early in the game,
for apparent reasons.
> but just means KERNEL_IBRS, which means only kernel is protected,
> userspace is still unprotected.
Yes, that was always the intent with IBRS: enable on kernel entry and
disable on exit.
Thx.
--
Regards/Gruss,
Boris.
https://people.kernel.org/tglx/notes-about-netiquette
