On Mon, Feb 20, 2023 at 10:01:57AM -0800, KP Singh wrote:
> Well, we disable IBRS userspace (this is KENREL_IBRS), because it is
> slow. Now if a user space process wants to protect itself from cross
> thread training, it should be able to do it, either by turning STIBP
> always on or using a prctl to enable. With the current logic, it's
> unable to do so.
Ofcourse it can:
[SPECTRE_V2_USER_PRCTL] = "User space: Mitigation: STIBP via prctl",
we did this at the time so that a userspace process can control it via
prctl().
So, maybe you should explain what you're trying to accomplish in detail
and where it fails...
--
Regards/Gruss,
Boris.
https://people.kernel.org/tglx/notes-about-netiquette
