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Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Mike Snitzer , Jens Axboe , Ritesh Harjani , Chuck Lever Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-nfs@vger.kernel.org, linux-mm@kvack.org, Jeff Layton X-Mailer: b4 0.14.3 X-Developer-Signature: v=1; a=openpgp-sha256; l=1084; i=jlayton@kernel.org; h=from:subject:message-id; bh=6R6WN7QnLwKTUc2bC5H1Z4sYb5q8DLb1p7kKZ09YbHE=; b=owEBbQKS/ZANAwAKAQAOaEEZVoIVAcsmYgBqAcRw/d2G69PENt9dpII3eX7moPHrfcJfJVKpz U2jJnpt2f+JAjMEAAEKAB0WIQRLwNeyRHGyoYTq9dMADmhBGVaCFQUCagHEcAAKCRAADmhBGVaC FSjED/9B+1yQ1WSrNNdIhOxP4U+WPleq5eEldlJUXnR4U9UuQ/YPgnW30Hq1QkSq5ty0m8y/KE4 AEYuxkB8dn2QqREbvLR8O7Loa4ODbWwRbjyX3f5XwYhpKUvCcnHvOU024VkKdYL8Pvr5gcLv9UC b6mg0hgxPVyVLGawrZZ5g8X1zeiuOXcqLt1sGzX7IuUP2R+DnXGx7nw81hYT/HEP8AexYoFNEOr sIgKtTqr6iFoMCfFjTuTxHqdDCUXuAWBzV1ie8uvQuQbOrthLwlL6TEUXee/qh+6tduhiOBqw// 7t7m4rkTuh9jXRhQeJi6vzWJeAr+q7jdkguKYL1yndnzZxiLFeHlZMRog8bqFBG3UFfWSWR/vXP a10nr0XN7wpWsqyYIAF61tPIoODLz6N+3TMIt4Tr5X8sEFWLTKXzxyM8DecOhtmfIK5oB3CkVtm gDXuKXhYHwWmybz+d5fZEiZ7lUEMZswt/pcFGR1Y30S3UEuSrPsKom3Ddki1Ljf4+qAnv+1m8OY Vm80xMmiAGz50Pecc46IEeqOMTJras52eY6RFSRyD9TMsZs2xh4gcWZPTiI+UrSbLEvOZdyXki/ VGlyMDvbI/Teu3yd5oE/IAJQQ1Z0EFRT1WJbkdlCPRZ9GWDZEZrXF6OaNgaCNhVq/NqXKPh7P3N aewMDqixNIZwhpg== X-Developer-Key: i=jlayton@kernel.org; a=openpgp; fpr=4BC0D7B24471B2A184EAF5D3000E684119568215 X-Stat-Signature: 6hy8iz7q9cga7nz1qzm1uzkkf6b8jckw X-Rspamd-Server: rspam01 X-Rspamd-Queue-Id: 00A27C0002 X-Rspam-User: X-HE-Tag: 1778500725-469530 X-HE-Meta: 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 orwtEoum HBYZbtbXBajkTPPiKSiaz/ER4nzgCrSRdI4gafSDET3btFufyAkAk4S3HZm5f86d50crchzedaelDRY3lZWeFhUuGDqeAB0cICAplm0WA8XefvZC3fsFp2cttbCJ1heR3d/yqJqu74KXGpSI+OI6ve5TkAk5Dc/ARoU5r5VS/xQt0i6/S7OoaDJQQGOb+hJjxBXMVHVMfTrSmmK+BQcIGetgqQtYgMqHdFY5rOXawzG/GdWGA2xQndSV8GInta1FgvHOgHscOwwrHqDBKsfaMk9kkNAwC2PsLIXPAfZ8eaw7Zg/YTYNTUc1RzkEwPZ8atxmq1qI0AJg6efNS6G3MtWtOe4jp+JssYELLPLDIlDNnFKms= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: __split_folio_to_order() copies page flags from the original folio to newly created sub-folios using an explicit allowlist, but PG_dropbehind is not included. When a large folio with PG_dropbehind set is split, only the head sub-folio retains the flag; all tail sub-folios silently lose it and will not be reclaimed eagerly after writeback completes. Add PG_dropbehind to the flag copy mask so that the drop-behind hint is preserved across folio splits. Fixes: a323281cdfec ("mm: add PG_dropbehind folio flag") Assisted-by: Claude:claude-opus-4-6 Signed-off-by: Jeff Layton --- mm/huge_memory.c | 1 + 1 file changed, 1 insertion(+) diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 970e077019b7..e01917b14d1a 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -3642,6 +3642,7 @@ static void __split_folio_to_order(struct folio *folio, int old_order, (1L << PG_arch_3) | #endif (1L << PG_dirty) | + (1L << PG_dropbehind) | LRU_GEN_MASK | LRU_REFS_MASK)); if (handle_hwpoison && -- 2.54.0