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 C986A56852B; Wed, 9 Sep 2026 14:41:54 +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=1788964916; cv=none; b=d0ut4SGAclxCw/6EHR8FIiAkDAnc0Q0WbuC8PCO32DdWV2CLGKAp8pQ3uiZA5To1BG/oYRUUtJr6Jt9XJmoMS9miqDSMCNl55Q6PLVKulY4qJ9VrQcl7n60V/r8ngNNnahU9AyJu7D8mgVG76LGNJovcCnRhFrsybCUEgvbpkls= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788964916; c=relaxed/simple; bh=x8dgZr2lZrEEFm9JCtaZhZX3BMw/MLPbu2xVpTGX0Ns=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=ebABOAJtc0q5nqVMZzyTLRFUb2OrxXKJcsY6GqQRC1OYUyZSEgEq0bk1jGxOqM+/H5wrUHZKlP42MIPp2+5oBUNxfGz1Fr8uDnmdPLgieFQp/U4b3qBZFBKzXOkPokvShdNmZVUIJJCiMd62239eBRx++98LUSxlLO9AgOGmXEg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=PLdmbxT1; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="PLdmbxT1" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 09A631F00A3A; Wed, 9 Sep 2026 14:41:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1788964914; bh=qFhysndJOG9drmjneZ8ZmUeb3AFBjSxVNAi6mWKDLlM=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=PLdmbxT1Im6BeaerHW+1IKePLSzaaeSOvdujBQndos+oQtjGzVYeu8NzQ51Sl0SP5 unuN5hqflsxtku0Kl+HTeBmFFe6RvOQoMXotJUU6HoUjljjEN7ku/Z0/ktJnZnybRY CpEw0HUnBrO5vhQSxRgkblZaEservI4EyRuPO4tI= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Muchun Song , Oscar Salvador , Frank van der Linden , "Aneesh Kumar K.V" , David Hildenbrand , "Liam R. Howlett" , Lorenzo Stoakes , Madhavan Srinivasan , Michael Ellerman , "Mike Rapoport (Microsoft)" , Nicholas Piggin , "Oscar Salvador (SUSE)" , "Ritesh Harjani (IBM)" , Usama Arif , Vlastimil Babka , Andrew Morton , Sasha Levin Subject: [PATCH 6.18 562/583] mm/hugetlb_vmemmap: fix __hugetlb_vmemmap_optimize_folios() Date: Wed, 9 Sep 2026 15:44:07 +0200 Message-ID: <20260909134257.146213820@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260909134237.773280130@linuxfoundation.org> References: <20260909134237.773280130@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Muchun Song [ Upstream commit 6e25c6a9c7eff141ecfc966ecdb7801db2a8810e ] __hugetlb_vmemmap_optimize_folios() uses incorrect arguments when handling bootmem HugeTLB folios. The section number passed to register_page_bootmem_memmap() is derived from the vmemmap virtual address of folio->page instead of the folio PFN, so the bootmem memmap metadata can be registered against the wrong section. The helper is also given HUGETLB_VMEMMAP_RESERVE_SIZE even though it expects a page count, not a size in bytes. In addition, the write-protect range is based on pages_per_huge_page(h), which does not cover the full HugeTLB vmemmap area and can leave part of the shared tail vmemmap mapping writable. Fix the section lookup to use folio_pfn(folio), use HUGETLB_VMEMMAP_RESERVE_PAGES when registering the reserved memmap pages, and use hugetlb_vmemmap_size(h) for the write-protect range. Link: https://lore.kernel.org/20260612035903.2468601-3-songmuchun@bytedance.com Fixes: 752fe17af693 ("mm/hugetlb: add pre-HVO framework") Signed-off-by: Muchun Song Acked-by: Oscar Salvador Reviewed-by: Frank van der Linden Cc: "Aneesh Kumar K.V" Cc: David Hildenbrand Cc: Liam R. Howlett Cc: Lorenzo Stoakes Cc: Madhavan Srinivasan Cc: Michael Ellerman Cc: Mike Rapoport (Microsoft) Cc: Nicholas Piggin Cc: Oscar Salvador (SUSE) Cc: "Ritesh Harjani (IBM)" Cc: Usama Arif Cc: Vlastimil Babka Cc: Signed-off-by: Andrew Morton Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- mm/hugetlb_vmemmap.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) --- a/mm/hugetlb_vmemmap.c +++ b/mm/hugetlb_vmemmap.c @@ -615,12 +615,12 @@ static void __hugetlb_vmemmap_optimize_f * mirrored tail page structs RO. */ spfn = (unsigned long)&folio->page; - epfn = spfn + pages_per_huge_page(h); + epfn = spfn + hugetlb_vmemmap_size(h); vmemmap_wrprotect_hvo(spfn, epfn, folio_nid(folio), HUGETLB_VMEMMAP_RESERVE_SIZE); - register_page_bootmem_memmap(pfn_to_section_nr(spfn), + register_page_bootmem_memmap(pfn_to_section_nr(folio_pfn(folio)), &folio->page, - HUGETLB_VMEMMAP_RESERVE_SIZE); + HUGETLB_VMEMMAP_RESERVE_PAGES); continue; }