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=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=ham 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 8D73EC83004 for ; Tue, 28 Apr 2020 03:54:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6D791206B6 for ; Tue, 28 Apr 2020 03:54:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726318AbgD1DyP (ORCPT ); Mon, 27 Apr 2020 23:54:15 -0400 Received: from foss.arm.com ([217.140.110.172]:45390 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725917AbgD1DyP (ORCPT ); Mon, 27 Apr 2020 23:54:15 -0400 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 5A40B31B; Mon, 27 Apr 2020 20:54:14 -0700 (PDT) Received: from [10.163.70.197] (unknown [10.163.70.197]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 3C8713F73D; Mon, 27 Apr 2020 20:54:05 -0700 (PDT) Subject: Re: [mm/debug] fa6726c1e7: kernel_BUG_at_include/linux/mm.h To: Qian Cai Cc: kernel test robot , Stephen Rothwell , Christophe Leroy , Catalin Marinas , Ingo Molnar , Mike Rapoport , Vineet Gupta , Will Deacon , Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman , Heiko Carstens , Vasily Gorbik , Christian Borntraeger , Thomas Gleixner , Ingo Molnar , Borislav Petkov , "H. Peter Anvin" , "Kirill A. Shutemov" , Paul Walmsley , Palmer Dabbelt , Andrew Morton , LKML , lkp@lists.01.org References: <096a07fc-4525-feb6-5658-40bcffbd0a58@arm.com> From: Anshuman Khandual Message-ID: Date: Tue, 28 Apr 2020 09:23:37 +0530 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 04/28/2020 08:21 AM, Qian Cai wrote: > > >> On Apr 27, 2020, at 10:35 PM, Anshuman Khandual wrote: >> >> Letting CONFIG_DEBUG_VM_PGTABLE enabled via CONFIG_EXPERT for unsupported >> platforms i.e without ARCH_HAS_DEBUG_VM_PGTABLE, was a conscious decision >> meant to expand it's adaptability and coverage without requiring any code >> (i.e Kconfig) change. The easier it is to enable the test on unsupported >> platforms right now, more folks are likely to try it out thus increasing >> it's probability to get fixed on those platforms. That is a valid enough >> reason to have CONFIG_EXPERT based enablement method, IMHO. Also even with >> CONFIG_EXPERT set, CONFIG_DEBUG_VM_PGTABLE does not get enabled by default >> automatically. > > No, I am talking about PAE. There is a distinction between known broken that nobody cares (like arm32) and in-progress/unknown status (like s390). > > Also, it is not very nice to introduce regressions for robots when testing PAE because they always select CONFIG__EXPERT and CONFIG_DEBUG_VM. Okay, will add X86_PAE to the explicitly disabled list along with IA64 and ARM. ---- From: Anshuman Khandual Date: Tue, 28 Apr 2020 04:30:04 +0100 Subject: [PATCH 3/3] mm/debug/pgtable: Completely disable X86_PAE Completely disable X86_PAE, even via CONFIG_EXPERT. Signed-off-by: Anshuman Khandual --- lib/Kconfig.debug | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 6a492e32579a..79e097a2285f 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -697,7 +697,7 @@ config DEBUG_VM_PGFLAGS config DEBUG_VM_PGTABLE bool "Debug arch page table for semantics compliance" depends on MMU - depends on !IA64 && !ARM + depends on !IA64 && !ARM && !X86_PAE depends on ARCH_HAS_DEBUG_VM_PGTABLE || EXPERT default y if ARCH_HAS_DEBUG_VM_PGTABLE && DEBUG_VM help -- Hello Andrew/Stephen, Could you please fold the above patch in linux-next. Also please do let me know if I should respin the series as well. Thank you. - Anshuman