Re: [RFC PATCH 1/2] x86/ibpb: Skip IBPB when we switch back to same user process

[Andi Kleen]

Andy Lutomirski <l...@kernel.org> writes:
>
> That being said, just stashing last_user_mm without any refcounting
> should be fine.

If last_user_mm is freed and reallocated by a different process,
then that would miss the IPBP incorrectly.

-Andi