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 14D4B51E43F for ; Fri, 4 Sep 2026 18:35:11 +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=1788546922; cv=none; b=g3tJkBYHm2JTFWHePgriO0D8kU0OFHQ4nn9PRzhXIRn/ubUIxL6jHPO7Xi0QIA8S0SloqtvLi6qj3RWtjSrynwo6Wm3CU+yF/ub+0Ucs3A+MYMnQ1Hwtja91R/+dlQtFXOSpOLFUVYIPf5Ty0buSgEnEZaRdyEFwMVNhZiSjf24= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788546922; c=relaxed/simple; bh=SwB5XgCNwZBZphq1fUqPaSUe3DwbNAy3L97ncGtq5ck=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=AtykZU2RYlLOyjNAOEG1HNpuUs90Fz8LX59EHMHd66FsjAsnQlCRbC4CNDmu1TcoUGub8lxSXAJM4s2tVbQlkHNXM62AeUq7kE0MJwnjHq/LGhFXDF7TiD4VIM8O3G/aJNKkmifHppm6M5oZ2ERGssLyZ8qetsqU6eFYnjeJ1mc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Hq5oj68G; 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="Hq5oj68G" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 459341F00A3F; Fri, 4 Sep 2026 18:35:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1788546908; bh=fp63aQ2sKP0Ix60opvhlrR66crkLY0dNLr90wEWC/ww=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=Hq5oj68GsQxd44Dwy7wqpicBt6N2Feze+0IgJRLOWWZe8ddEuZDSUbJ/6aZuvz0nY ZAWVXl04Vp33V9KHwGDa/CL4i63RH7Ag1pIQMzwriLTUoydYzkReddTmp+JoCANki7 YoczAXdvzo8Ro8aoZCNgNmXHj9HjXW90I7fKw2XPKeQWmli8phEkPs+fyzx99QgQm5 8oHbJHLMrojpjhhALa5IeGU1hqbpZDRLOO3z1WzPxtN9F89rK2Nbk5rdJ7JNZAhSPD lk87jLCWQxvNdoDoyifpKmLcOLF4hAJZjet5v3/MXZVrYMXixZiKZobLlMfKVNxxmd yBrUAyzyq4v3Q== From: Sasha Levin To: stable@vger.kernel.org Cc: Dev Jain , "David Hildenbrand (Arm)" , Muchun Song , Alistair Popple , Andi Kleen , Anshuman Khandual , Byungchul Park , Catalin Marinas , Dave Hansen , Gregory Price , Harry Yoo , "Huang, Ying" , Jann Horn , Josh Poimboeuf , Joshua Hahn , Kiryl Shutsemau , Lance Yang , "Liam R. Howlett" , Lorenzo Stoakes , Matthew Brost , Mel Gorman , Naoya Horiguchi , Oscar Salvador , Pedro Falcato , Rakie Kim , Ralph Campbell , Rik van Riel , Ryan Roberts , Vlastimil Babka , Will Deacon , Zi Yan , Andrew Morton , Sasha Levin Subject: [PATCH 5.15.y 2/2] mm/page_vma_mapped: use huge_ptep_get() for hugetlb Date: Fri, 4 Sep 2026 14:35:02 -0400 Message-ID: <20260904183502.1323253-2-sashal@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260904183502.1323253-1-sashal@kernel.org> References: <2026090326-clutch-freeness-d94a@gregkh> <20260904183502.1323253-1-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: Dev Jain [ Upstream commit e87df0d5d6962bde50f55f6d02b779daa394f894 ] check_pte() is the final validation step in page_vma_mapped_walk(). It reads pvmw->pte with ptep_get() to decide whether the entry maps the PFN range being walked. For hugetlb VMAs, that pointer refers to a hugetlb entry. 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. Use huge_ptep_get() to dereference a huge pte pointer. Link: https://lore.kernel.org/20260703114202.365553-6-dev.jain@arm.com Fixes: ace71a19cec5 ("mm: introduce page_vma_mapped_walk()") Signed-off-by: Dev Jain Acked-by: David Hildenbrand (Arm) Reviewed-by: Muchun Song 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 Signed-off-by: Sasha Levin --- mm/page_vma_mapped.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/mm/page_vma_mapped.c b/mm/page_vma_mapped.c index 3f003623eef45..e07f4b80d44b1 100644 --- a/mm/page_vma_mapped.c +++ b/mm/page_vma_mapped.c @@ -87,7 +87,13 @@ static inline bool pfn_is_match(struct page *page, unsigned long pfn) static bool check_pte(struct page_vma_mapped_walk *pvmw) { unsigned long pfn; - pte_t ptent = ptep_get(pvmw->pte); + pte_t ptent; + + if (is_vm_hugetlb_page(pvmw->vma)) + ptent = huge_ptep_get(pvmw->vma->vm_mm, pvmw->address, + pvmw->pte); + else + ptent = ptep_get(pvmw->pte); if (pvmw->flags & PVMW_MIGRATION) { swp_entry_t entry; -- 2.53.0