From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DE3A8BE63 for ; Sat, 25 Jul 2026 01:37:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784943466; cv=none; b=SxtTfq5uXvY2NzEJ4LPb9m7FHo8D9y/rGBG5MfHtkQvI08gKj9YJXMduKlMXW637EbyJShnLKP7eMssEJcK7QJZf5bev9xyHif4OWa21FSxrQ9cQIfPUHw2J/6UIOhsGKw9cpoBF9W6ztUrtRKohgIo8O1YDi1dZ2+QjIvN+Svw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784943466; c=relaxed/simple; bh=VSQhrBMLwtw4iGVGoaTvsQtoK8FUTibMQ9/kh+BUjwA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=aIJCp1P9Lnb6rWH3Kod5NCoEpA9/6c5i8/20MAAxOzo4sXB/3AkzroHgNH+S/LcewSIX4+RDUlQ8e/9fJ5O0vYolbZ3Y/X2nNCU2qLlaBk5mBeik3S1fdzSwNo6hCwwU7zJKweq+ME7Dl1LQl5WFc/f5q1v3syaCxj2RzSyOoBM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Kpg6oNsb; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Kpg6oNsb" Received: by smtp.kernel.org (Postfix) with ESMTPSA id DA8EB1F000E9; Sat, 25 Jul 2026 01:37:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1784943464; bh=DDQw0pWhH/nwKSNR13SEjoy+2ZZPvbAnDACCQkTXkYE=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=Kpg6oNsb1rnEq8rEoQBs4x0TAa2BkCpvRm8pr6FQGNRJVR2gBTFg/vt6q64ZBesxf xCYYvdXlct7sSly8NSGvAs/M5qqOvfCdoOZDVS+uVIyHzzwXyIY7+ZaWbbmvD5Ftas Z2aylp4QhdWdW3iOn4mVsbowBUTFydCjHzxeHhMfuRCLE4aTn+IB4HrvN/pXW91hHk 9exK3bHZEKnOIcduunkXp1SJyHyka8sarSSVVz6dcjY53y3LD9mtBWISA439l6Pc2L TSjO7WvEdDDWze79I/1CjMOYHqFuefXd1DutoR9NDrm5Un6ZAsixz0HBfnv3uqYmqH ra/VEmMOxqSiQ== From: Sasha Levin To: stable@vger.kernel.org Cc: Muchun Song , "Mike Rapoport (Microsoft)" , Oscar Salvador , "David Hildenbrand (Arm)" , "Liam R. Howlett" , "Aneesh Kumar K.V" , Joao Martins , Lorenzo Stoakes , Madhavan Srinivasan , Michael Ellerman , Michal Hocko , Nicholas Piggin , Suren Baghdasaryan , Vlastimil Babka , Andrew Morton , Sasha Levin Subject: [PATCH 6.12.y] mm/mm_init: fix pageblock migratetype for ZONE_DEVICE compound pages Date: Fri, 24 Jul 2026 21:37:41 -0400 Message-ID: <20260725013741.1892750-1-sashal@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <2026072014-stowaway-nebulizer-98db@gregkh> References: <2026072014-stowaway-nebulizer-98db@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Muchun Song [ Upstream commit 94405c6136839f7c462249c8b4b957bcb9527a9d ] The memmap_init_zone_device() function only initializes the migratetype of the first pageblock of a compound page. If the compound page size exceeds pageblock_nr_pages (e.g., 1GB hugepages with 2MB pageblocks), subsequent pageblocks in the compound page remain uninitialized. Move the migratetype initialization out of __init_zone_device_page() and into a separate pageblock_migratetype_init_range() function. This iterates over the entire PFN range of the memory, ensuring that all pageblocks are correctly initialized. Also remove the stale confusing comment about MEMINIT_HOTPLUG above the migratetype setting since it is an obsolete relic from commit 966cf44f637e ("mm: defer ZONE_DEVICE page initialization to the point where we init pgmap") and no longer makes sense here. Link: https://lore.kernel.org/20260428081855.1249045-6-songmuchun@bytedance.com Fixes: c4386bd8ee3a ("mm/memremap: add ZONE_DEVICE support for compound pages") Signed-off-by: Muchun Song Reviewed-by: Mike Rapoport (Microsoft) Reviewed-by: Oscar Salvador Acked-by: David Hildenbrand (Arm) Acked-by: Liam R. Howlett Cc: "Aneesh Kumar K.V" Cc: Joao Martins Cc: Lorenzo Stoakes Cc: Madhavan Srinivasan Cc: Michael Ellerman Cc: Michal Hocko Cc: Nicholas Piggin Cc: Suren Baghdasaryan Cc: Vlastimil Babka Cc: Signed-off-by: Andrew Morton Signed-off-by: Sasha Levin --- mm/mm_init.c | 34 +++++++++++++++++++--------------- 1 file changed, 19 insertions(+), 15 deletions(-) diff --git a/mm/mm_init.c b/mm/mm_init.c index 1450b2bb98ee32..2b8b57af2bc57f 100644 --- a/mm/mm_init.c +++ b/mm/mm_init.c @@ -650,6 +650,20 @@ static inline void fixup_hashdist(void) static inline void fixup_hashdist(void) {} #endif /* CONFIG_NUMA */ +#ifdef CONFIG_ZONE_DEVICE +static __meminit void pageblock_migratetype_init_range(unsigned long pfn, + unsigned long nr_pages, int migratetype) +{ + const unsigned long end = pfn + nr_pages; + + for (pfn = pageblock_align(pfn); pfn < end; pfn += pageblock_nr_pages) { + set_pageblock_migratetype(pfn_to_page(pfn), migratetype); + if (IS_ALIGNED(pfn, PAGES_PER_SECTION)) + cond_resched(); + } +} +#endif + #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT static inline void pgdat_set_deferred_range(pg_data_t *pgdat) { @@ -999,21 +1013,6 @@ static void __ref __init_zone_device_page(struct page *page, unsigned long pfn, page->pgmap = pgmap; page->zone_device_data = NULL; - /* - * Mark the block movable so that blocks are reserved for - * movable at startup. This will force kernel allocations - * to reserve their blocks rather than leaking throughout - * the address space during boot when many long-lived - * kernel allocations are made. - * - * Please note that MEMINIT_HOTPLUG path doesn't clear memmap - * because this is done early in section_activate() - */ - if (pageblock_aligned(pfn)) { - set_pageblock_migratetype(page, MIGRATE_MOVABLE); - cond_resched(); - } - /* * ZONE_DEVICE pages are released directly to the driver page allocator * which will set the page count to 1 when allocating the page. @@ -1105,6 +1104,9 @@ void __ref memmap_init_zone_device(struct zone *zone, __init_zone_device_page(page, pfn, zone_idx, nid, pgmap); + if (IS_ALIGNED(pfn, PAGES_PER_SECTION)) + cond_resched(); + if (pfns_per_compound == 1) continue; @@ -1112,6 +1114,8 @@ void __ref memmap_init_zone_device(struct zone *zone, compound_nr_pages(pfn, altmap, pgmap)); } + pageblock_migratetype_init_range(start_pfn, nr_pages, MIGRATE_MOVABLE); + pr_debug("%s initialised %lu pages in %ums\n", __func__, nr_pages, jiffies_to_msecs(jiffies - start)); } -- 2.53.0