linux-kernel - Re: [PATCH 02/10] mm: convert core mm to mm_flags

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Message-ID: <8092b7e7-935d-438d-be16-28ffcd8bb7f7@lucifer.local>
Date: Wed, 13 Aug 2025 05:11:15 +0100
From: Lorenzo Stoakes <lorenzo.stoakes@...cle.com>
To: Andrew Morton <akpm@...ux-foundation.org>
Cc: Alexander Gordeev <agordeev@...ux.ibm.com>,
        Gerald Schaefer <gerald.schaefer@...ux.ibm.com>,
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Subject: Re: [PATCH 02/10] mm: convert core mm to mm_flags_*() accessors

On Tue, Aug 12, 2025 at 03:52:30PM -0700, Andrew Morton wrote:
> On Tue, 12 Aug 2025 16:44:11 +0100 Lorenzo Stoakes <lorenzo.stoakes@...cle.com> wrote:
>
> > As part of the effort to move to mm->flags becoming a bitmap field, convert
> > existing users to making use of the mm_flags_*() accessors which will, when
> > the conversion is complete, be the only means of accessing mm_struct flags.
> >
> > This will result in the debug output being that of a bitmap output, which
> > will result in a minor change here, but since this is for debug only, this
> > should have no bearing.
> >
> > Otherwise, no functional changes intended.
>
> Code is obviously buggy - you cannot possibly have tested it.
>
> --- a/mm/khugepaged.c~mm-convert-core-mm-to-mm_flags_-accessors-fix
> +++ a/mm/khugepaged.c
> @@ -1459,7 +1459,7 @@ static void collect_mm_slot(struct khuge
>  		/*
>  		 * Not strictly needed because the mm exited already.
>  		 *
> -		 * mm_clear(mm, MMF_VM_HUGEPAGE);
> +		 * mm_flags_clear(MMF_VM_HUGEPAGE, mm);
>  		 */
>
>  		/* khugepaged_mm_lock actually not necessary for the below */
>
> there, fixed.

Haha thanks!

>
> I applied the series to mm-new, thanks.  Emails were suppressed out of
> kindness.
>

Yes, probably for the best :)

Cheers, Lorenzo