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charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Rspam-User: X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: 73D2B10000A X-Stat-Signature: ab4w3pwgbmifuq18ayk3heozmf5jaurc X-HE-Tag: 1751357533-480193 X-HE-Meta: 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 EDRgT/YK 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 30.06.25 18:14, Zi Yan wrote: > On 30 Jun 2025, at 12:01, Lorenzo Stoakes wrote: > >> On Mon, Jun 30, 2025 at 02:59:46PM +0200, David Hildenbrand wrote: >>> Let the page freeing code handle clearing the page type. >> >> Why is this advantageous? We want to keep the page marked offline for longer? >> >>> >>> Acked-by: Zi Yan >>> Acked-by: Harry Yoo >>> Signed-off-by: David Hildenbrand >> >> On assumption this UINT_MAX stuff is sane :)) I mean this is straightforward I >> guess: > > This is how page type is cleared. > See: https://elixir.bootlin.com/linux/v6.15.4/source/include/linux/page-flags.h#L1013. > > I agree with you that patch 4 should have a comment in free_pages_prepare() > about what the code is for and why UINT_MAX is used. I can add a comment /* Reset the page_type -> _mapcount to -1 */ To patch #4. -- Cheers, David / dhildenb