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 2FC7733939D; Fri, 31 Jul 2026 02:43:37 +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=1785465821; cv=none; b=aTX7//nvha2SqpqaZZYxb2Gj3/h0/YAdyASc/bl6+nyQM6GrV7yk5E3Y8ice6lmoRu7PwGNtNUafTRaWRVez9Bx8DYnRqjQ4xjYiMUYXs1++9kbIchsZIv5wgeJtHuR+ZHErK1vnWXrk/btARbUKvh8sqqJFMn8gpGzOLriq5+U= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785465821; c=relaxed/simple; bh=OizBgQgk5q36x+8aHyWsYl29aseTrM6Vdb95u+pW/zU=; h=Date:To:From:Subject:Message-Id; b=X/xpya81nZX5+0t1bDLHnkHCLPoQJPRxUNFUgsmjdoeiM15nTedfvK36poEst+VLjOJaUccH5gwD9x6hPa/mp4BoYfnudq9cV8Ym0uM7zGXUkExsmeynMyoSc9WBeg/XB/uXNOcwglvpTnONnBxRzYUhyj+vWdaMWILpvkwGAgU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b=kPZGSOIk; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="kPZGSOIk" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 06B251F000E9; Fri, 31 Jul 2026 02:43:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=korg; t=1785465817; bh=G9+/ytHgr5ogs6keKTvsf7uYQkckAce1uCsCVNyOkjo=; h=Date:To:From:Subject; b=kPZGSOIkBXhu06GR4uiOnLcR8EFv5p+v7bAyoXLh/rW+XWHSzts4M4ruuypAc7cQt LF97/qi3YW2JuOtlPnjs58MyYWSqPeewTHeIExbuL+Ar9Miwk+ULmIE9e7rydZh+QX oiRzzZD9V5yy8e5eaZPSQnxKLffONOwZ1JasBT60= Date: Thu, 30 Jul 2026 19:43:36 -0700 To: mm-commits@vger.kernel.org,ziy@nvidia.com,ying.huang@linux.alibaba.com,will@kernel.org,vbabka@kernel.org,stable@vger.kernel.org,ryan.roberts@arm.com,riel@surriel.com,rcampbell@nvidia.com,rakie.kim@sk.com,pfalcato@suse.de,osalvador@suse.de,nao.horiguchi@gmail.com,muchun.song@linux.dev,mel@csn.ul.ie,matthew.brost@intel.com,ljs@kernel.org,liam@infradead.org,lance.yang@linux.dev,kas@kernel.org,jpoimboe@kernel.org,joshua.hahnjy@gmail.com,j-nomura@ce.jp.nec.com,jannh@google.com,harry@kernel.org,gourry@gourry.net,david@kernel.org,dave.hansen@intel.com,catalin.marinas@arm.com,byungchul@sk.com,apopple@nvidia.com,anshuman.khandual@arm.com,ak@linux.intel.com,dev.jain@arm.com,akpm@linux-foundation.org From: Andrew Morton Subject: [merged mm-stable] mm-rmap-use-huge_ptep_get-in-try_to_unmap_one.patch removed from -mm tree Message-Id: <20260731024337.06B251F000E9@smtp.kernel.org> Precedence: bulk X-Mailing-List: mm-commits@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: The quilt patch titled Subject: mm/rmap: use huge_ptep_get() in try_to_unmap_one() has been removed from the -mm tree. Its filename was mm-rmap-use-huge_ptep_get-in-try_to_unmap_one.patch This patch was dropped because it was merged into the mm-stable branch of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm ------------------------------------------------------ From: Dev Jain Subject: mm/rmap: use huge_ptep_get() in try_to_unmap_one() Date: Fri, 3 Jul 2026 11:41:55 +0000 Patch series "Fix incorrect access of hugetlb pte entries", v3. There are various places which use ptep_get() to get the pte entry corresponding to a hugetlb folio. Some arches (like s390) have special handling to compute the pteval, so they provide huge_ptep_get(). Use this helper consistently. Additionally, some code paths may provide huge_ptep_get with an unaligned address. This is a problem on arm64 (I checked other arches and it looks fine for them), which is fixed in patch 1. The fix is made to be backport-friendly: the cleaner fix would be to perhaps pass the hstate to huge_ptep_get() - that is wider churn and we can do that later. This patch (of 5): try_to_unmap_one() handles hugetlb folios when memory failure needs to replace a poisoned hugetlb mapping with a hwpoison entry. In that case page_vma_mapped_walk() returns the pte pointer to the hugetlb folio in pvmw.pte, but the code reads it with ptep_get(). On arches which provide their own huge_ptep_get() to dereference a huge pte pointer, accessing via ptep_get() would cause pte_pfn(), pte_present() etc to misbehave. It is not clear whether this has a trivially visible effect to userspace. Just use huge_ptep_get() for dereferencing a huge pte pointer. Link: https://lore.kernel.org/20260703114202.365553-1-dev.jain@arm.com Link: https://lore.kernel.org/20260703114202.365553-3-dev.jain@arm.com Fixes: c7ab0d2fdc84 ("mm: convert try_to_unmap_one() to use page_vma_mapped_walk()") Signed-off-by: Dev Jain Reported-by: David Hildenbrand Reviewed-by: Muchun Song Acked-by: David Hildenbrand (Arm) Cc: Alistair Popple Cc: Andi Kleen Cc: Anshuman Khandual Cc: Byungchul Park Cc: Catalin Marinas Cc: Dave Hansen Cc: Gregory Price Cc: Harry Yoo Cc: "Huang, Ying" Cc: Jann Horn Cc: Josh Poimboeuf Cc: Joshua Hahn Cc: Jun'ichi "Nick" Nomura Cc: Kiryl Shutsemau Cc: Lance Yang Cc: Liam R. Howlett Cc: Lorenzo Stoakes Cc: Matthew Brost Cc: Mel Gorman Cc: Naoya Horiguchi Cc: Oscar Salvador Cc: Pedro Falcato Cc: Rakie Kim Cc: Ralph Campbell Cc: Rik van Riel Cc: Ryan Roberts Cc: Vlastimil Babka Cc: Will Deacon Cc: Zi Yan Cc: Signed-off-by: Andrew Morton --- include/linux/hugetlb.h | 2 ++ mm/rmap.c | 16 ++++++++++------ 2 files changed, 12 insertions(+), 6 deletions(-) --- a/include/linux/hugetlb.h~mm-rmap-use-huge_ptep_get-in-try_to_unmap_one +++ a/include/linux/hugetlb.h @@ -1270,6 +1270,8 @@ static inline void hugetlb_count_sub(lon { } +pte_t huge_ptep_get(struct mm_struct *mm, unsigned long addr, pte_t *ptep); + static inline pte_t huge_ptep_clear_flush(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep) { --- a/mm/rmap.c~mm-rmap-use-huge_ptep_get-in-try_to_unmap_one +++ a/mm/rmap.c @@ -2095,14 +2095,19 @@ static bool try_to_unmap_one(struct foli /* Unexpected PMD-mapped THP? */ VM_BUG_ON_FOLIO(!pvmw.pte, folio); - /* - * Handle PFN swap PTEs, such as device-exclusive ones, that - * actually map pages. - */ - pteval = ptep_get(pvmw.pte); + address = pvmw.address; + if (folio_test_hugetlb(folio)) { + pteval = huge_ptep_get(mm, address, pvmw.pte); + } else { + pteval = ptep_get(pvmw.pte); + } if (likely(pte_present(pteval))) { pfn = pte_pfn(pteval); } else { + /* + * Handle PFN swap PTEs, such as device-exclusive ones, + * that actually map pages. + */ const softleaf_t entry = softleaf_from_pte(pteval); pfn = softleaf_to_pfn(entry); @@ -2110,7 +2115,6 @@ static bool try_to_unmap_one(struct foli } subpage = folio_page(folio, pfn - folio_pfn(folio)); - address = pvmw.address; anon_exclusive = folio_test_anon(folio) && PageAnonExclusive(subpage); _ Patches currently in -mm which might be from dev.jain@arm.com are mm-rmap-convert-page-folio-for-hwpoison-checks.patch mm-rmap-add-try_to_unmap_poisoned_hugetlb_one.patch mm-rmap-refactor-some-code-around-lazyfree-folio-unmapping.patch mm-rmap-refactor-anon-folio-unmap-in-try_to_unmap_one.patch mm-rmap-add-anon-folio-unmap-dispatcher.patch mm-memory-move-pte_install_uffd_wp_if_needed-into-memoryc.patch mm-memory-batch-set-uffd-wp-markers-during-zapping.patch mm-rmap-batch-unmap-file-folios-belonging-to-uffd-wp-vmas.patch