linux-kernel - Re: [PATCH 10/10] mm: replace mm->flags with bitmap entirely and set to 64 bits

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Message-ID: <7fe98bec-a750-4005-a308-ae7a7afc0e3b@lucifer.local>
Date: Tue, 26 Aug 2025 14:22:43 +0100
From: Lorenzo Stoakes <lorenzo.stoakes@...cle.com>
To: David Hildenbrand <david@...hat.com>
Cc: Andrew Morton <akpm@...ux-foundation.org>,
        Alexander Gordeev <agordeev@...ux.ibm.com>,
        Gerald Schaefer <gerald.schaefer@...ux.ibm.com>,
        Heiko Carstens <hca@...ux.ibm.com>, Vasily Gorbik <gor@...ux.ibm.com>,
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Subject: Re: [PATCH 10/10] mm: replace mm->flags with bitmap entirely and set
 to 64 bits

On Tue, Aug 26, 2025 at 03:14:46PM +0200, David Hildenbrand wrote:
> On 12.08.25 17:44, Lorenzo Stoakes wrote:
> > Now we have updated all users of mm->flags to use the bitmap accessors,
> > repalce it with the bitmap version entirely.
> >
> > We are then able to move to having 64 bits of mm->flags on both 32-bit and
> > 64-bit architectures.
> >
> > We also update the VMA userland tests to ensure that everything remains
> > functional there.
> >
> > No functional changes intended, other than there now being 64 bits of
> > available mm_struct flags.
> >
> > Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@...cle.com>
> > ---
> >   include/linux/mm.h               | 12 ++++++------
> >   include/linux/mm_types.h         | 14 +++++---------
> >   include/linux/sched/coredump.h   |  2 +-
> >   tools/testing/vma/vma_internal.h | 19 +++++++++++++++++--
> >   4 files changed, 29 insertions(+), 18 deletions(-)
>
> The vma test code duplication is still making me sad ... but I'll get over
> it I'm sure.

Yeah ;) I do want to work on seeing if I can do something more about this in
future as I intend to do more with those tests but all time-dependent obviously!

>
> Acked-by: David Hildenbrand <david@...hat.com>

Cheers!

>
> --
> Cheers
>
> David / dhildenb
>