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 838DA4A0F0D for ; Thu, 3 Sep 2026 16:59:29 +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=1788454770; cv=none; b=l2dPWxGJPzL7t+/wkWze9cNBR8bgw4sBiXpqKgRMgdLrkolUbnvBwsAczHzoSAE843A/0AVjrBWSGOH7kAZSoP6U50alU1miW+t0r53s1s/Pt9Z6RYUD6q6YU5OfgwNRwoV6Xh+oGNWJOGw9N+z3sN5SbOnQ9jSArUwYsgVJkzA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788454770; c=relaxed/simple; bh=uFwyPrMw+wg63FARYv+aKemuKy65rBTozFyoK4nXqtk=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=r0tGOYO6dlMf/EWpaBvGyPnYO2KHfvKwbli72jeqOLEs9dsNjPVjgWEde8BDynmfTzsQjA31t8o/RZBud7r44MqoR5bNv+ydOeoD9kpH9FqAgrmx+MCXtoG0Ho5EGfmd9CmWJabnwFGJgvCrpRvda8pVTU7IyqCsgmec0KgrxZo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=T3rZ3Rz+; 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="T3rZ3Rz+" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9C9931F000E9; Thu, 3 Sep 2026 16:59:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1788454769; bh=L+u4Dj38mBfWpdCmqi/7NMOVH4Xq3lE6fPMrPoqbWTo=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=T3rZ3Rz++o1UOdqSxY6D7MGQ2JKwCEOS1JKAd7PkLpNYYEhbqtHQP7nY2+sTbffXA C5EtOfKXyu1D4t98oOLuhKE3iDnxSPJuHpPpj+Tn6UMCXXIkKs+Wq1za3WK/nK1BoJ yb21CvAhM60kEGhj0LY/toajyaHLytcZYmDP/DalN9MfZWCc8lPO728bU8l+s0T7lR Ol+38ttVIv2zyEN+VO8mCc1a7oST5LxMI4ZI86lZnJnNz2MA3UFgRZx5gOnXSBIxId 4tNX/1tbdypqtnfroxGhGbm2KaRPnoMrDfLTIYkongwtsnxFZ2vuuD9Ye5eDObuyNv aKCdAMPrECaLA== From: Sasha Levin To: stable@vger.kernel.org Cc: 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.y 5/5] mm/hugetlb_vmemmap: fix __hugetlb_vmemmap_optimize_folios() Date: Thu, 3 Sep 2026 12:59:14 -0400 Message-ID: <20260903165914.1085906-5-sashal@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260903165914.1085906-1-sashal@kernel.org> References: <2026090320-cufflink-ambitious-4582@gregkh> <20260903165914.1085906-1-sashal@kernel.org> 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 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 --- mm/hugetlb_vmemmap.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/mm/hugetlb_vmemmap.c b/mm/hugetlb_vmemmap.c index f96d00a3ef2ee..0afacf93ca4cd 100644 --- a/mm/hugetlb_vmemmap.c +++ b/mm/hugetlb_vmemmap.c @@ -615,12 +615,12 @@ static void __hugetlb_vmemmap_optimize_folios(struct hstate *h, * 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; } -- 2.53.0