Re: [PATCH] man/man2/mremap.2: describe multiple mapping move, shrink

[Lorenzo Stoakes <lorenzo.stoakes@oracle.com>]

On Fri, Jul 25, 2025 at 10:44:59PM +0200, Alejandro Colomar wrote:
> Hi Lorenzo,
>
> On Wed, Jul 23, 2025 at 06:46:34PM +0100, Lorenzo Stoakes wrote:
> > There is pre-existing logic that appears to be undocumented for an mremap()
> > shrink operation, where it turns out that the usual 'input range must span
> > a single mapping' requirement no longer applies.
> >
> > In fact, it turns out that the input range specified by [old_address,
> > old_size) may span any number of mappings, as long old_address resides at
> > or within a mapping and [old_address, new_size) spans only a single
> > mapping.
> >
> > Explicitly document this.
> >
> > In addition, document the new behaviour introduced in Linux 6.17 whereby it
> > is now possible to move multiple mappings in a single operation, as long as
> > the operation is purely a move, that is old_size is equal to new_size and
> > MREMAP_FIXED is specified.
>
> Please separate the new behavior into a separate patch.  Each patch
> should change one thing only.

OK will split and send two separate patches. Since this will cause merge pain
otherwise, I'll send it as a series.