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Subject: Re: [PATCH v2 06/32] mm/page_vma_mapped: delete bogosity in
 page_vma_mapped_walk()
Date:   Mon, 10 Jul 2023 21:47:46 -0400
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Content-Type: text/plain

On 8 Jun 2023, at 21:12, Hugh Dickins wrote:

> Revert commit a7a69d8ba88d ("mm/thp: another PVMW_SYNC fix in
> page_vma_mapped_walk()"): I was proud of that "Aha!" commit at the time,
> but in revisiting page_vma_mapped_walk() for pte_offset_map() failure,
> that block raised a doubt: and it now seems utterly bogus.  The prior
> map_pte() has taken ptl unconditionally when PVMW_SYNC: I must have
> forgotten that when making the change.  It did no harm, but could not
> have fixed a BUG or WARN, and is hard to reconcile with coming changes.
>
> Signed-off-by: Hugh Dickins <hughd@google.com>

LGTM. Reviewed-by: Zi Yan <ziy@nvidia.com>

--
Best Regards,
Yan, Zi

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