Re: [PATCH v4] mm: Fix a hmm_range_fault() livelock / starvation problem

[Andrew Morton <akpm@linux-foundation.org>]

On Mon, 09 Feb 2026 15:47:38 +0100 Thomas Hellström <thomas.hellstrom@linux.intel.com> wrote:

> @Alistair, any chance of an R-B for the below version?

Yes please.

> @Andrew, will this go through the -mm tree or alternaltively an ack for
> merging through drm-xe-fixes?

Either works.  I'll grab a copy.  It you want to take this via drm then
I'll drop the mm.git copy once the drm tree's version appears in linux-next.

Acked-by: Andrew Morton <akpm@linux-foundation.org>

> > The lru_add_drain_all() function requires a short work-item

Pet peeve: s/the foo() function/foo()/g.  It's just as good!

> > --- a/mm/memory.c
> > +++ b/mm/memory.c
> > @@ -4684,7 +4684,8 @@ vm_fault_t do_swap_page(struct vm_fault *vmf)
> >  				unlock_page(vmf->page);
> >  				put_page(vmf->page);
> >  			} else {
> > -				pte_unmap_unlock(vmf->pte, vmf->ptl);
> > +				pte_unmap(vmf->pte);
> > +				softleaf_entry_wait_on_locked(entry, vmf->ptl);
> >  			}
> >  		} else if (softleaf_is_hwpoison(entry)) {
> >  			ret = VM_FAULT_HWPOISON;

So apart from the rename, this is the whole patch.  This got nicer!