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Date: Tue, 7 May 2024 10:17:07 +0200
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Subject: Re: [PATCH v4 2/3] mm/rmap: integrate PMD-mapped folio splitting into
 pagewalk loop
To: Lance Yang <ioworker0@gmail.com>,
 Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: akpm@linux-foundation.org, willy@infradead.org, sj@kernel.org,
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 minchan@kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org
References: <20240501042700.83974-1-ioworker0@gmail.com>
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From: David Hildenbrand <david@redhat.com>
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>>>
>>> +             if (!pvmw.pte && (flags & TTU_SPLIT_HUGE_PMD)) {
>>> +                     /*
>>> +                      * We temporarily have to drop the PTL and start once
>>> +                      * again from that now-PTE-mapped page table.
>>> +                      */
>>> +                     split_huge_pmd_locked(vma, range.start, pvmw.pmd, false,
>>> +                                           folio);
>>> +                     pvmw.pmd = NULL;
>>> +                     spin_unlock(pvmw.ptl);
>>
>> IMO, you should also make the 'pvmw.ptl = NULL;' after unlocking as
>> page_vma_mapped_walk() did, in case some corner case met.
> 
> Yep, I'll also set pvmw.ptl to NULL here if any corner cases arise.
> 

This series already resides in mm-stable. I asked Andrew to remove it 
for now. If that doesn't work, we'll need fixup patches to address any 
review feedback.

-- 
Cheers,

David / dhildenb