Re: [PATCH v3 2/4] mm/damon/ops-common: atomically test and clear young on ptes and pmds

From: Yu Zhao
Date: Fri Jun 02 2023 - 13:36:23 EST


On Fri, Jun 2, 2023 at 11:14 AM Ryan Roberts <ryan.roberts@xxxxxxx> wrote:
>
> On 02/06/2023 17:35, Yu Zhao wrote:
> > On Fri, Jun 2, 2023 at 3:30 AM Ryan Roberts <ryan.roberts@xxxxxxx> wrote:
> >>
> >> It is racy to non-atomically read a pte, then clear the young bit, then
> >> write it back as this could discard dirty information. Further, it is
> >> bad practice to directly set a pte entry within a table. Instead
> >> clearing young must go through the arch-provided helper,
> >> ptep_test_and_clear_young() to ensure it is modified atomically and to
> >> give the arch code visibility and allow it to check (and potentially
> >> modify) the operation.
> >>
> >> Fixes: 3f49584b262c ("mm/damon: implement primitives for the virtual memory address spaces").
> >
> > Just to double check: was "Cc: stable@xxxxxxxxxxxxxxx" overlooked or
> > deemed unnecessary?
>
> It was overlooked - incompetance strikes again! I was intending to cc the whole
> series. What's the best way to fix this? Can I just add stable in cc on reply to
> the cover letter or will I have to resend the lot?

Resending the whole series would be more reliable for the process (and
easier for Andrew). You might want to include a few new
reviewed/acked-bys anyway (I just acked the next patch).