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=-13.6 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=unavailable 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 E07E8C433E6 for ; Tue, 1 Sep 2020 04:05:25 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 49C9920719 for ; Tue, 1 Sep 2020 04:05:25 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 49C9920719 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from bilbo.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 4BgYPt5xcSzDqWG for ; Tue, 1 Sep 2020 14:05:22 +1000 (AEST) Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=arm.com (client-ip=217.140.110.172; helo=foss.arm.com; envelope-from=anshuman.khandual@arm.com; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=arm.com Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lists.ozlabs.org (Postfix) with ESMTP id 4BgYN06FMJzDqQw for ; Tue, 1 Sep 2020 14:03:43 +1000 (AEST) 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 C839430E; Mon, 31 Aug 2020 21:03:41 -0700 (PDT) Received: from [10.163.69.171] (unknown [10.163.69.171]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id C7EAD3F68F; Mon, 31 Aug 2020 21:03:36 -0700 (PDT) From: Anshuman Khandual Subject: Re: [PATCH v3 12/13] mm/debug_vm_pgtable/hugetlb: Disable hugetlb test on ppc64 To: "Aneesh Kumar K.V" , linux-mm@kvack.org, akpm@linux-foundation.org References: <20200827080438.315345-1-aneesh.kumar@linux.ibm.com> <20200827080438.315345-13-aneesh.kumar@linux.ibm.com> Message-ID: <6191e77f-c3b7-21ea-6dbd-eecc09735923@arm.com> Date: Tue, 1 Sep 2020 09:33:04 +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: <20200827080438.315345-13-aneesh.kumar@linux.ibm.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-arch@vger.kernel.org, linux-s390@vger.kernel.org, Christophe Leroy , x86@kernel.org, Mike Rapoport , Qian Cai , Gerald Schaefer , Vineet Gupta , linux-snps-arc@lists.infradead.org, linuxppc-dev@lists.ozlabs.org, linux-arm-kernel@lists.infradead.org Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On 08/27/2020 01:34 PM, Aneesh Kumar K.V wrote: > The seems to be missing quite a lot of details w.r.t allocating > the correct pgtable_t page (huge_pte_alloc()), holding the right > lock (huge_pte_lock()) etc. The vma used is also not a hugetlb VMA. > > ppc64 do have runtime checks within CONFIG_DEBUG_VM for most of these. > Hence disable the test on ppc64. Would really like this to get resolved in an uniform and better way instead, i.e a modified hugetlb_advanced_tests() which works on all platforms including ppc64. In absence of a modified version, I do realize the situation here, where DEBUG_VM_PGTABLE test either runs on ppc64 or just completely remove hugetlb_advanced_tests() from other platforms as well. > > Signed-off-by: Aneesh Kumar K.V > --- > mm/debug_vm_pgtable.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/mm/debug_vm_pgtable.c b/mm/debug_vm_pgtable.c > index a188b6e4e37e..21329c7d672f 100644 > --- a/mm/debug_vm_pgtable.c > +++ b/mm/debug_vm_pgtable.c > @@ -813,6 +813,7 @@ static void __init hugetlb_basic_tests(unsigned long pfn, pgprot_t prot) > #endif /* CONFIG_ARCH_WANT_GENERAL_HUGETLB */ > } > > +#ifndef CONFIG_PPC_BOOK3S_64 > static void __init hugetlb_advanced_tests(struct mm_struct *mm, > struct vm_area_struct *vma, > pte_t *ptep, unsigned long pfn, > @@ -855,6 +856,7 @@ static void __init hugetlb_advanced_tests(struct mm_struct *mm, > pte = huge_ptep_get(ptep); > WARN_ON(!(huge_pte_write(pte) && huge_pte_dirty(pte))); > } > +#endif In the worst case if we could not get a new hugetlb_advanced_tests() test that works on all platforms, this might be the last fallback option. In which case, it will require a proper comment section with a "FIXME: ", explaining the current situation (and that #ifdef is temporary in nature) and a hugetlb_advanced_tests() stub when CONFIG_PPC_BOOK3S_64 is enabled. > #else /* !CONFIG_HUGETLB_PAGE */ > static void __init hugetlb_basic_tests(unsigned long pfn, pgprot_t prot) { } > static void __init hugetlb_advanced_tests(struct mm_struct *mm, > @@ -1065,7 +1067,9 @@ static int __init debug_vm_pgtable(void) > pud_populate_tests(mm, pudp, saved_pmdp); > spin_unlock(ptl); > > +#ifndef CONFIG_PPC_BOOK3S_64 > hugetlb_advanced_tests(mm, vma, ptep, pte_aligned, vaddr, prot); > +#endif #ifdef will not be required here as there would be a stub definition for hugetlb_advanced_tests() when CONFIG_PPC_BOOK3S_64 is enabled. > > spin_lock(&mm->page_table_lock); > p4d_clear_tests(mm, p4dp); > But again, we should really try and avoid taking this path.