From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7B133C433E7 for ; Fri, 16 Oct 2020 02:41:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 27A1320897 for ; Fri, 16 Oct 2020 02:41:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1602816108; bh=EDZeoik6ip2wmYr+ORIrFSiuIfWG+o83Omgn/oxpoKo=; h=Date:From:To:Subject:In-Reply-To:Reply-To:List-ID:From; b=pKi1JW4lwssc1AD/x9OZ41ptefpCNs9BCxrpNxYCYkjrf4pw970CeAbx689ue+kxB 3rMEBQDIHIHShww8F//V7Etj2OhVudztnIUDhB03iTqoSFDzxMNLYP2d/vwf2Ux2Ch x2X1ASfbcZp8OvrNi5iT9golhMXKT78z/bJ+FZyY= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2404291AbgJPClr (ORCPT ); Thu, 15 Oct 2020 22:41:47 -0400 Received: from mail.kernel.org ([198.145.29.99]:57260 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728688AbgJPClr (ORCPT ); Thu, 15 Oct 2020 22:41:47 -0400 Received: from localhost.localdomain (c-73-231-172-41.hsd1.ca.comcast.net [73.231.172.41]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 424ED208C7; Fri, 16 Oct 2020 02:41:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1602816107; bh=EDZeoik6ip2wmYr+ORIrFSiuIfWG+o83Omgn/oxpoKo=; h=Date:From:To:Subject:In-Reply-To:From; b=trjcTOAEZC1T27MYrsVrx0bw4l42SG5icTi0L3zOrjxaCqAiaHmTq58y7CwAb7x9b eUxtiaNvgsBPtXV2BwzMZeo4Q3aDB1aKpxmePowyEirlSpJjHq0TVFZO2fYINrDN/P uot6gQS+zUxVIaDYjn/CFH8AvTb5jNe+GQIMksIs= Date: Thu, 15 Oct 2020 19:41:45 -0700 From: Andrew Morton To: akpm@linux-foundation.org, aneesh.kumar@linux.ibm.com, anshuman.khandual@arm.com, aou@eecs.berkeley.edu, christophe.leroy@csgroup.eu, linux-mm@kvack.org, linux@roeck-us.net, mm-commits@vger.kernel.org, mpe@ellerman.id.au, natechancellor@gmail.com, palmer@dabbelt.com, paul.walmsley@sifive.com, torvalds@linux-foundation.org Subject: [patch 014/156] mm/debug_vm_pgtable: avoid none pte in pte_clear_test Message-ID: <20201016024145.Fdx4rvWB9%akpm@linux-foundation.org> In-Reply-To: <20201015192732.f448da14e9854c7cb7299956@linux-foundation.org> User-Agent: s-nail v14.8.16 Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org From: "Aneesh Kumar K.V" Subject: mm/debug_vm_pgtable: avoid none pte in pte_clear_test pte_clear_tests operate on an existing pte entry. Make sure that is not a none pte entry. [aneesh.kumar@linux.ibm.com: avoid kernel crash with riscv] Link: https://lkml.kernel.org/r/20201015033206.140550-1-aneesh.kumar@linux.ibm.com Link: https://lkml.kernel.org/r/20200902114222.181353-14-aneesh.kumar@linux.ibm.com Signed-off-by: Aneesh Kumar K.V Reviewed-by: Anshuman Khandual Cc: Christophe Leroy Cc: Michael Ellerman Cc: Nathan Chancellor Cc: Guenter Roeck Cc: Paul Walmsley Cc: Albert Ou Cc: Palmer Dabbelt Signed-off-by: Andrew Morton --- mm/debug_vm_pgtable.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) --- a/mm/debug_vm_pgtable.c~mm-debug_vm_pgtable-avoid-none-pte-in-pte_clear_test +++ a/mm/debug_vm_pgtable.c @@ -542,12 +542,15 @@ static void __init pgd_populate_tests(st #endif /* PAGETABLE_P4D_FOLDED */ static void __init pte_clear_tests(struct mm_struct *mm, pte_t *ptep, - unsigned long vaddr) + unsigned long pfn, unsigned long vaddr, + pgprot_t prot) { - pte_t pte = ptep_get(ptep); + pte_t pte = pfn_pte(pfn, prot); pr_debug("Validating PTE clear\n"); +#ifndef CONFIG_RISCV pte = __pte(pte_val(pte) | RANDOM_ORVALUE); +#endif set_pte_at(mm, vaddr, ptep, pte); barrier(); pte_clear(mm, vaddr, ptep); @@ -998,7 +1001,7 @@ static int __init debug_vm_pgtable(void) ptl = pte_lockptr(mm, pmdp); spin_lock(ptl); - pte_clear_tests(mm, ptep, vaddr); + pte_clear_tests(mm, ptep, pte_aligned, vaddr, prot); pte_advanced_tests(mm, vma, ptep, pte_aligned, vaddr, prot); pte_unmap_unlock(ptep, ptl); _