Re: [PULL] topic/iomem-mmap-vs-gup

From: Sean Christopherson
Date: Mon May 10 2021 - 13:57:26 EST


+Paolo

On Mon, May 10, 2021, Jason Gunthorpe wrote:
> On Mon, May 10, 2021 at 04:55:39PM +0200, Daniel Vetter wrote:
>
> > yeah vfio is still broken for the case I care about. I think there's
> > also some questions open still about whether kvm really uses
> > mmu_notifier in all cases correctly,
>
> IIRC kvm doesn't either.

Yep, KVM on x86 has a non-trivial number of flows that don't properly hook into
the mmu_notifier. Paolo is working on fixing the problem, but I believe the
rework won't be ready until 5.14.