Re: [PATCH v13 07/13] iommu/vt-d: Add SVA domain support

[Baolu Lu]

On 2022/9/23 21:07, Jason Gunthorpe wrote:
> On Fri, Sep 23, 2022 at 08:41:56PM +0800, Baolu Lu wrote:
> > On 2022/9/23 20:15, Jason Gunthorpe wrote:
> > > On Fri, Sep 23, 2022 at 10:21:51AM +0800, Baolu Lu wrote:
> > >
> > > > At the beginning of this project, I wanted to consolidate the mm
> > > > notifications into the core. However, ARM SMMUv3 and Intel handle the mm
> > > > notifications a little differently. Then I decided to do this work
> > > > separately from the current series.
> > > It doesn't look really different..
> > They are essentially the same, but slightly different. For example, arm
> > smmuv3 provides .free_notifier, and I don't think it could be merged to
> > the release callback.
> free_notifier allows to use mmu_notifier_put() instead of
> mmu_notifier_unregister() which avoids a synchronize_rcu() penalty on
> teardown. Intel should copy the same design.

Ah! Thanks for the guide. I will head in this direction.

Best regards,
baolu