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[128.59.177.174]) by smtp.gmail.com with ESMTPSA id 6a1803df08f44-91040673ce0sm122105496d6.25.2026.09.08.08.16.43 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 08 Sep 2026 08:16:43 -0700 (PDT) From: Tal Zussman Date: Tue, 08 Sep 2026 11:16:32 -0400 Subject: [PATCH v2 2/8] mm/huge_memory: add a comment to the open-coded swap entry Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20260908-folio_swap_entry-v2-2-ee6d01dfa5e1@columbia.edu> References: <20260908-folio_swap_entry-v2-0-ee6d01dfa5e1@columbia.edu> In-Reply-To: <20260908-folio_swap_entry-v2-0-ee6d01dfa5e1@columbia.edu> To: Andrew Morton , Chris Li , Kairui Song , Kemeng Shi , Nhat Pham , Baoquan He , Barry Song , Youngjun Park , David Hildenbrand , Zi Yan , Baolin Wang , "Liam R. 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Add a comment explaining this. Signed-off-by: Tal Zussman --- mm/huge_memory.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/mm/huge_memory.c b/mm/huge_memory.c index d1ce061601bc..1fabdcbd8c8f 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -3763,6 +3763,10 @@ static void __split_folio_to_order(struct folio *folio, int old_order, */ VM_WARN_ON_ONCE_PAGE(new_folio->private, new_head); + /* + * Not all folio fields are valid during a split, so open-code + * the swap entry rather than using folio_swap_entry(). + */ if (folio_test_swapcache(folio)) new_folio->swap.val = folio->swap.val + i; -- 2.39.5