Re: [PATCH v2 0/2] mm: stop calling pmd_folio() on special PMDs

[Gregory Price]

On Fri, Sep 11, 2026 at 09:25:03PM -0700, Andrew Morton wrote:
> On Fri, 11 Sep 2026 23:48:31 -0400 Gregory Price <gourry@xxxxxxxxxx> wrote:
> 
> > Reproducer
> > ==========
> > 
> > No hardware needed.  An out of tree module stands in for the drivers above:
> > three misc devices, each with a ->huge_fault calling vmf_insert_pfn_pmd(),
> > plus VM_HUGEPAGE so the fault path takes the PMD branch.
> 
> I take it there's no known way of triggering this in current mainline?

As far as I can tell there are no in-tree modules that reach this state,
at least not obviously.  

~Gregory