RE: [PATCH 1/3] iommu/vt-d: Use 128-bit atomic updates for context entries

[Tian, Kevin]

> From: Baolu Lu <baolu.lu@xxxxxxxxxxxxxxx>
> Sent: Thursday, January 15, 2026 11:27 AM
> 
> On 1/14/26 15:54, Tian, Kevin wrote:
> >
> > Then this may be split into three patches:
> >
> > - change context_clear_entry() to be atomic, to fix the teardown path
> > - add present bit check in other functions in this patch, to scrutinize the
> >    attach path
> > - change those functions to be atomic, as a clean up
> 
> Perhaps this also paves the way for enabling hitless replace in the
> attach_dev path?
> 

I didn't get it. attach/replace are different paths and iommu core will
reject an attach request for a device which is already attached...