Re: [PATCH 15/15] mm: add mmap_action_map_kernel_pages[_full]()

["Lorenzo Stoakes (Oracle)" <ljs@kernel.org>]

On Thu, Mar 12, 2026 at 04:15:26PM -0700, Randy Dunlap wrote:
>
> On 3/12/26 1:27 PM, Lorenzo Stoakes (Oracle) wrote:
>
> > Finally, we update the VMA tests accordingly to reflect the changes.
>
> IMO we could omit the word "we" 5 times above.
> (but no change is required)
>
> > diff --git a/include/linux/mm.h b/include/linux/mm.h
> > index 88f42faeb377..88ad5649c02d 100644
> > --- a/include/linux/mm.h
> > +++ b/include/linux/mm.h
>
> > +/**
> > + * range_is_subset - Is the specified inner range a subset of the outer range?
> > + * @outer_start: The start of the outer range.
> > + * @outer_end: The exclusive end of the outer range.
> > + * @inner_start: The start of the inner range.
> > + * @inner_end: The exclusive end of the inner range.
> > + *
> > + * Returns %true if [inner_start, inner_end) is a subset of [outer_start,
>
>     * Returns:
> (for kernel-doc)

Ack

>
> > + * outer_end), otherwise %false.
> > + */
> > +static inline bool range_is_subset(unsigned long outer_start,
> > +				   unsigned long outer_end,
> > +				   unsigned long inner_start,
> > +				   unsigned long inner_end)
> > +{
> > +	return outer_start <= inner_start && inner_end <= outer_end;
> > +}
> > +
> > +/**
> > + * range_in_vma - is the specified [@start, @end) range a subset of the VMA?
> > + * @vma: The VMA against which we want to check [@start, @end).
> > + * @start: The start of the range we wish to check.
> > + * @end: The exclusive end of the range we wish to check.
> > + *
> > + * Returns %true if [@start, @end) is a subset of [@vma->vm_start,
>
>     * Returns:

Ack

>
> > + * @vma->vm_end), %false otherwise.
> > + */
> >  static inline bool range_in_vma(const struct vm_area_struct *vma,
> >  				unsigned long start, unsigned long end)
> >  {
> > -	return (vma && vma->vm_start <= start && end <= vma->vm_end);
> > +	if (!vma)
> > +		return false;
> > +
> > +	return range_is_subset(vma->vm_start, vma->vm_end, start, end);
> > +}
> > +
> > +/**
> > + * range_in_vma_desc - is the specified [@start, @end) range a subset of the VMA
> > + * described by @desc, a VMA descriptor?
> > + * @desc: The VMA descriptor against which we want to check [@start, @end).
> > + * @start: The start of the range we wish to check.
> > + * @end: The exclusive end of the range we wish to check.
> > + *
> > + * Returns %true if [@start, @end) is a subset of [@desc->start, @desc->end),
>
>     * Returns:

Ack, I think in general I've seen (or believe I've seen :) other cases without
the colon, so was kinda imitating, but I may also be imagining that ;)

>
> > + * %false otherwise.
> > + */
> > +static inline bool range_in_vma_desc(const struct vm_area_desc *desc,
> > +				     unsigned long start, unsigned long end)
> > +{
> > +	if (!desc)
> > +		return false;
> > +
> > +	return range_is_subset(desc->start, desc->end, start, end);
> >  }
>
> --
> ~Randy
>

Will also fold these changes into the respin!

Cheers, Lorenzo