From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id DE58B1DDC35; Thu, 25 Jun 2026 11:30:48 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782387050; cv=none; b=M8L4Ecy8gK75P1mJWDIlaACSF4Y0tNgH0CR4LrVvdDaMS3xYIzziXFdPgz+uAmwm5DUjqQ7gEedzE5VE8j+yWizQ4QNqmt6yxEV65PycWORcMLl9fwKFCCKZ8NPKiQKCig7xRegqBjPyS1lcbNOhdkmfWkr/JPxgRpsmpmuHFC8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782387050; c=relaxed/simple; bh=YVYXx7DeCmRXI/6Xkq+kjiu0y3ZMotg0IHB7MU6Rf+0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=E94dl0GihI7gPtM/EfRp+AIUHs6ryY0IsFYyt1yppmXWJxBjzI/6MgA+SDwxU0X3KNIK2Li6S4rrMu0J7wYtvp6EMaQJ7fFrD/4eo22tgTsU30EmOu79KBAwC4gKrJSeYmX59H6n3ATZiOBKfNcr//0hVzW2HYOJ0M49XGE4QDs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b=lPhXMZix; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b="lPhXMZix" Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id B3B9932C5; Thu, 25 Jun 2026 04:30:43 -0700 (PDT) Received: from cesw-amp-gbt-1s-m12830-01.blr.arm.com (cesw-amp-gbt-1s-m12830-01.blr.arm.com [10.164.195.31]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 62A6A3F62B; Thu, 25 Jun 2026 04:30:39 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1782387048; bh=YVYXx7DeCmRXI/6Xkq+kjiu0y3ZMotg0IHB7MU6Rf+0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=lPhXMZixeJNC/52qJLXM5cTBoxRiSy5jpouJtE3546YakjPVG02EkqA0y0Pttu6f4 vEubb3v+HokNHqXS9u+EdjoFlvwz0SEaMIbm0h2LhhvM0p8h4sr3ODmRvGEXhBb643 TyLvs/lWTDqBE7EgRklZegpCtyYIMNccFix02v8M= From: Dev Jain To: muchun.song@linux.dev, osalvador@suse.de, akpm@linux-foundation.org, ljs@kernel.org, david@kernel.org, liam@infradead.org Cc: Dev Jain , riel@surriel.com, vbabka@kernel.org, harry@kernel.org, jannh@google.com, lance.yang@linux.dev, kas@kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, rcampbell@nvidia.com, apopple@nvidia.com, ziy@nvidia.com, matthew.brost@intel.com, joshua.hahnjy@gmail.com, rakie.kim@sk.com, byungchul@sk.com, gourry@gourry.net, ying.huang@linux.alibaba.com, mel@csn.ul.ie, nao.horiguchi@gmail.com, ak@linux.intel.com, j-nomura@ce.jp.nec.com, pfalcato@suse.de, dave.hansen@intel.com, tglx@kernel.org, jpoimboe@kernel.org, ryan.roberts@arm.com, anshuman.khandual@arm.com, stable@vger.kernel.org Subject: [PATCH 4/5] mm/page_vma_mapped: use huge_ptep_get() for hugetlb Date: Thu, 25 Jun 2026 11:29:53 +0000 Message-ID: <20260625112955.3254283-5-dev.jain@arm.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260625112955.3254283-1-dev.jain@arm.com> References: <20260625112955.3254283-1-dev.jain@arm.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 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. Fixes: ace71a19cec5 ("mm: introduce page_vma_mapped_walk()") Cc: stable@vger.kernel.org Signed-off-by: Dev Jain --- 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 2ccbabfb2cc17..18e1d341f463c 100644 --- a/mm/page_vma_mapped.c +++ b/mm/page_vma_mapped.c @@ -107,7 +107,13 @@ static bool map_pte(struct page_vma_mapped_walk *pvmw, pmd_t *pmdvalp, static bool check_pte(struct page_vma_mapped_walk *pvmw, unsigned long pte_nr) { 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) { const softleaf_t entry = softleaf_from_pte(ptent); -- 2.43.0