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(p200300d82f40b30053f7d260aff47256.dip0.t-ipconnect.de. [2003:d8:2f40:b300:53f7:d260:aff4:7256]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-3a892e598ddsm9681774f8f.78.2025.06.30.01.16.27 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 30 Jun 2025 01:16:29 -0700 (PDT) Message-ID: <1fee1926-638b-4852-b98f-a0423a94b7f8@redhat.com> Date: Mon, 30 Jun 2025 10:16:26 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH RFC 07/29] mm/migrate: rename isolate_movable_page() to isolate_movable_ops_page() To: Harry Yoo Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-doc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, virtualization@lists.linux.dev, linux-fsdevel@vger.kernel.org, Andrew Morton , Jonathan Corbet , Madhavan Srinivasan , Michael Ellerman , Nicholas Piggin , Christophe Leroy , Jerrin Shaji George , Arnd Bergmann , Greg Kroah-Hartman , "Michael S. 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charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Stat-Signature: 6bzrydn87n951fc7ppfstot4w9o991tw X-Rspamd-Server: rspam01 X-Rspamd-Queue-Id: 3EAEF40008 X-Rspam-User: X-HE-Tag: 1751271396-419112 X-HE-Meta: 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 xN3RWgRO 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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 10:04, Harry Yoo wrote: > On Wed, Jun 18, 2025 at 07:39:50PM +0200, David Hildenbrand wrote: >> ... and start moving back to per-page things that will absolutely not be >> folio things in the future. Add documentation and a comment that the >> remaining folio stuff (lock, refcount) will have to be reworked as well. >> >> While at it, convert the VM_BUG_ON() into a WARN_ON_ONCE() and handle >> it gracefully (relevant with further changes), and convert a >> WARN_ON_ONCE() into a VM_WARN_ON_ONCE_PAGE(). >> >> Signed-off-by: David Hildenbrand >> --- > > Haha yeah, back to pages after folio conversion :P > But makes sense. > > Reviewed-by: Harry Yoo > > Side question: In the future, maybe we will be unable to tell whether > a page is compound or not, without first inspecting page->memdesc? > (e.g., struct slab could have an order and a pointer to the head page... > just imagining). Right, it's not really clear what we would do in the future, but for anything that allocates a memdesc, that is possible. We wouldn't even need the "head" + "tail" bit indication. For things without an allocated memdesc (e.g., PageOffline), maybe compound pages will simply not apply. Likely, the concept of compound pages as we knew it will go away. -- Cheers, David / dhildenb