Re: [PATCH 5/8] x86/mmu: Add mm-based PASID refcounting

[Luck, Tony]

On Fri, Sep 24, 2021 at 04:03:53PM -0700, Andy Lutomirski wrote:
> 1. The context switch code needs to resync PASID.  Unfortunately, this adds some overhead to every context switch, although a static_branch could minimize it for non-PASID users.

Any solution that adds to context switch time isn't going to meet
the definition of "perfect" either.

-Tony