Re: [PATCH 02/10] mm: convert core mm to mm_flags_*() accessors

From: Chris Mason
Date: Tue Sep 16 2025 - 16:05:39 EST


On Tue, 12 Aug 2025 16:44:11 +0100 Lorenzo Stoakes <lorenzo.stoakes@xxxxxxxxxx> 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.
>
> Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@xxxxxxxxxx>

[ ... ]

> diff --git a/mm/oom_kill.c b/mm/oom_kill.c
> index 25923cfec9c6..17650f0b516e 100644
> --- a/mm/oom_kill.c
> +++ b/mm/oom_kill.c

[ ... ]

> @@ -1251,7 +1251,7 @@ SYSCALL_DEFINE2(process_mrelease, int, pidfd, unsigned int, flags)
> * Check MMF_OOM_SKIP again under mmap_read_lock protection to ensure
> * possible change in exit_mmap is seen
> */
> - if (!test_bit(MMF_OOM_SKIP, &mm->flags) && !__oom_reap_task_mm(mm))
> + if (mm_flags_test(MMF_OOM_SKIP, mm) && !__oom_reap_task_mm(mm))
> ret = -EAGAIN;
> mmap_read_unlock(mm);
>

Hi Lorzeno, I think we lost a ! here.

claude found enough inverted logic in moved code that I did a new run with
a more explicit prompt for it, but this was the only new hit.

-chris