Re: [PATCH v3 1/1] iommu/sva: Invalidate KVA range on kernel TLB flush

[Jason Gunthorpe]

On Thu, Aug 28, 2025 at 11:56:00AM -0700, Dave Hansen wrote:
> I got a bit sick of sending constant emails on this one and just decided
> to hack it together myself. Here's roughly what I came up with.
> Completely untested. Changelogs are bare. Barely compiles:
> 
> > https://git.kernel.org/pub/scm/linux/kernel/git/daveh/devel.git/log/?h=kpte
> 
> I also didn't actually hook up the IOMMU flush yet.
> 
> The biggest single chunk of code is defining ptdesc_*_kernel(). The rest
> of it is painfully simple.

Seems not great to be casting ptdesc to folio just to use
folio_set_referenced(), I'm pretty sure that is no the direction
things are going in..

I'd set the flag yourself or perhaps use the memory of __page_mapping
to store a flag (but zero it before freeing).

Looks OK otherwise

Jason