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Peter Anvin" , Andrew Morton , David Hildenbrand , Lorenzo Stoakes , "Liam R . Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Kairui Song , Qi Zheng , Shakeel Butt , Barry Song , Axel Rasmussen , Yuanchu Xie , Wei Xu , linux-kernel@vger.kernel.org, linux-mm@kvack.org, Kaitao Cheng Content-Transfer-Encoding: 7bit Message-Id: <85F48B20-68C5-45D7-A8E7-27E601283743@linux.dev> References: <20260920070406.95354-1-kaitao.cheng@linux.dev> To: Kaitao Cheng X-Mailer: Apple Mail (2.3864.700.51.1.1) X-Rspam-User: X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: C1AA120004 X-Stat-Signature: 991hs4hoydbq6b8gdcgw4aiz47cxys9m X-HE-Tag: 1789898388-91478 X-HE-Meta: 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 a7cJjHDf pP3ikozCuOBcpeOLUalsuWKwz35Kp2pA6ymLLNqe44ScN6/woX3SpRfntfUIqschyDywX6FQ9OpSCeJGHjCkgliFlZg25wTdkT1fQDfGjWQgAyuHvbFhw2PP7tFTFS3WGGdI84ksg57MwQ82VM+jxs0r6BbHrsAOo5MjXNpJV+98AeHHn26Ex/ojNWUwRQCPUGKe6pJyQ6WSVnQJqirhZ+mw7sdBKHwk/iLkqRHSR1fv5KVCgVgT3YtsrptAoK9Vn6Z9aQQJsg1SchcCYh6MA7jnL7vqKUaQYXZeG+tzF5kjvyUC2K3EOO3ztXQ== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: > On Sep 20, 2026, at 15:04, Kaitao Cheng wrote: > > From: Kaitao Cheng > > Several MM paths identify classic sparse memory by testing > CONFIG_SPARSEMEM while also testing that CONFIG_SPARSEMEM_VMEMMAP is > disabled. Repeating the compound condition obscures the memory model being > selected and requires the local SECTION_IN_PAGE_FLAGS alias for the same > state. > > Add CONFIG_SPARSEMEM_CLASSIC as a hidden derived option and use it at the > conditional sites. Remove SECTION_IN_PAGE_FLAGS and test the new option > directly. > > The x86 32-bit vDSO build starts with the x86_64 configuration and then > undefines CONFIG_SPARSEMEM_VMEMMAP to emulate a 32-bit configuration. > Kconfig-derived symbols are not recomputed by the C preprocessor, so define > CONFIG_SPARSEMEM_CLASSIC there when CONFIG_SPARSEMEM is enabled. This > preserves the existing behavior. > > Signed-off-by: Kaitao Cheng Acked-by: Muchun Song Thanks.