Re: [tip: x86/mm] x86/mm/pat: Fix VM_PAT handling when fork() fails in copy_page_range()
From: Ingo Molnar
Date: Wed Mar 19 2025 - 18:08:57 EST
* David Hildenbrand <david@xxxxxxxxxx> wrote:
> On 19.03.25 12:01, Ingo Molnar wrote:
> >
> > * David Hildenbrand <david@xxxxxxxxxx> wrote:
> >
> > > > +void untrack_pfn_copy(struct vm_area_struct *dst_vma,
> > > > + struct vm_area_struct *src_vma)
> > > > +{
> > > > + resource_size_t paddr;
> > > > + unsigned long size;
> > > > +
> > > > + if (!(dst_vma->vm_flags & VM_PAT))
> > > > + return;
> > > > +
> > > > + /*
> > > > + * As the page tables might not have been copied yet, the PAT
> > > > + * information is obtained from the src VMA, just like during
> > > > + * track_pfn_copy().
> > > > + */
> > > > + if (get_pat_info(src_vma, &paddr, NULL)) {
> > > > + size = src_vma->vm_end - src_vma->vm_start;
> > > > + free_pfn_range(paddr, size);
> > > > }
> > >
> > > @Ingo, can you drop this patch for now?
> >
> > Done.
>
> I can resend the whole thing, or just the fixup suggested by Boris, just let
> me know.
Please do, thanks!
Thanks,
Ingo