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=-15.5 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,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 D6F08C4338F for ; Wed, 28 Jul 2021 07:32:03 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 677AE60E78 for ; Wed, 28 Jul 2021 07:32:03 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 677AE60E78 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvack.org Received: by kanga.kvack.org (Postfix) id 0B1FB6B0036; Wed, 28 Jul 2021 03:32:03 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 062F66B005D; Wed, 28 Jul 2021 03:32:03 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id E93E96B006C; Wed, 28 Jul 2021 03:32:02 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0174.hostedemail.com [216.40.44.174]) by kanga.kvack.org (Postfix) with ESMTP id 8A5806B0036 for ; Wed, 28 Jul 2021 03:31:57 -0400 (EDT) Received: from smtpin01.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 53A5A1803F93D for ; Wed, 28 Jul 2021 07:31:52 +0000 (UTC) X-FDA: 78411177264.01.B12BE3B Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by imf09.hostedemail.com (Postfix) with ESMTP id 965083002939 for ; Wed, 28 Jul 2021 07:31:51 +0000 (UTC) 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 7F4C41FB; Wed, 28 Jul 2021 00:31:50 -0700 (PDT) Received: from [10.163.65.183] (unknown [10.163.65.183]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 20C933F73D; Wed, 28 Jul 2021 00:31:46 -0700 (PDT) Subject: Re: [PATCH v4 01/12] mm/debug_vm_pgtable: Introduce struct pgtable_debug_args To: Gavin Shan , linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org, gerald.schaefer@linux.ibm.com, aneesh.kumar@linux.ibm.com, christophe.leroy@csgroup.eu, cai@lca.pw, catalin.marinas@arm.com, will@kernel.org, akpm@linux-foundation.org, chuhu@redhat.com, shan.gavin@gmail.com References: <20210727061401.592616-1-gshan@redhat.com> <20210727061401.592616-2-gshan@redhat.com> From: Anshuman Khandual Message-ID: <9977fea4-ff36-390a-3a5a-58f088dab111@arm.com> Date: Wed, 28 Jul 2021 13:02:36 +0530 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <20210727061401.592616-2-gshan@redhat.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 965083002939 Authentication-Results: imf09.hostedemail.com; dkim=none; dmarc=pass (policy=none) header.from=arm.com; spf=pass (imf09.hostedemail.com: domain of anshuman.khandual@arm.com designates 217.140.110.172 as permitted sender) smtp.mailfrom=anshuman.khandual@arm.com X-Stat-Signature: 6w1bt64r8rhsj8gcykgwyzgabtp97n6e X-HE-Tag: 1627457511-555776 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On 7/27/21 11:43 AM, Gavin Shan wrote: > In debug_vm_pgtable(), there are many local variables introduced to > track the needed information and they are passed to the functions for > various test cases. It'd better to introduce a struct as place holder > for these information. With it, what the tests functions need is the > struct. In this way, the code is simplified and easier to be maintained. > > Besides, set_xxx_at() could access the data on the corresponding pages > in the page table modifying tests. So the accessed pages in the tests > should have been allocated from buddy. Otherwise, we're accessing pages > that aren't owned by us. This causes issues like page flag corruption > or kernel crash on accessing unmapped page when CONFIG_DEBUG_PAGEALLOC > is enabled. > > This introduces "struct pgtable_debug_args". The struct is initialized > and destroyed, but the information in the struct isn't used yet. It will > be used in subsequent patches. > > Signed-off-by: Gavin Shan > --- > mm/debug_vm_pgtable.c | 280 +++++++++++++++++++++++++++++++++++++++++- > 1 file changed, 279 insertions(+), 1 deletion(-) > > diff --git a/mm/debug_vm_pgtable.c b/mm/debug_vm_pgtable.c > index 1c922691aa61..8c7361643166 100644 > --- a/mm/debug_vm_pgtable.c > +++ b/mm/debug_vm_pgtable.c > @@ -58,6 +58,37 @@ > #define RANDOM_ORVALUE (GENMASK(BITS_PER_LONG - 1, 0) & ~ARCH_SKIP_MASK) > #define RANDOM_NZVALUE GENMASK(7, 0) > > +struct pgtable_debug_args { > + struct mm_struct *mm; > + struct vm_area_struct *vma; > + > + pgd_t *pgdp; > + p4d_t *p4dp; > + pud_t *pudp; > + pmd_t *pmdp; > + pte_t *ptep; > + > + p4d_t *start_p4dp; > + pud_t *start_pudp; > + pmd_t *start_pmdp; > + pgtable_t start_ptep; > + > + unsigned long vaddr; > + pgprot_t page_prot; > + pgprot_t page_prot_none; > + > + bool is_contiguous_page; > + unsigned long pud_pfn; > + unsigned long pmd_pfn; > + unsigned long pte_pfn; > + > + unsigned long fixed_pgd_pfn; > + unsigned long fixed_p4d_pfn; > + unsigned long fixed_pud_pfn; > + unsigned long fixed_pmd_pfn; > + unsigned long fixed_pte_pfn; > +}; > + > static void __init pte_basic_tests(unsigned long pfn, int idx) > { > pgprot_t prot = protection_map[idx]; > @@ -955,8 +986,249 @@ static unsigned long __init get_random_vaddr(void) > return random_vaddr; > } > > +static void __init destroy_args(struct pgtable_debug_args *args) > +{ > + struct page *page = NULL; > + > + /* Free (huge) page */ > + if (IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE) && > + IS_ENABLED(CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD) && > + has_transparent_hugepage() && > + args->pud_pfn != ULONG_MAX) { > + if (args->is_contiguous_page) { > + free_contig_range(args->pud_pfn, > + (1 << (HPAGE_PUD_SHIFT - PAGE_SHIFT))); > + } else { > + page = pfn_to_page(args->pud_pfn); > + __free_pages(page, HPAGE_PUD_SHIFT - PAGE_SHIFT); > + } > + > + args->pud_pfn = ULONG_MAX; > + args->pmd_pfn = ULONG_MAX; > + args->pte_pfn = ULONG_MAX; > + } > + > + if (IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE) && > + has_transparent_hugepage() && > + args->pmd_pfn != ULONG_MAX) { > + if (args->is_contiguous_page) { > + free_contig_range(args->pmd_pfn, (1 << HPAGE_PMD_ORDER)); > + } else { > + page = pfn_to_page(args->pmd_pfn); > + __free_pages(page, HPAGE_PMD_ORDER); > + } > + > + args->pmd_pfn = ULONG_MAX; > + args->pte_pfn = ULONG_MAX; > + } > + > + if (args->pte_pfn != ULONG_MAX) { > + page = pfn_to_page(args->pte_pfn); > + __free_pages(page, 0); > + } > + > + /* Free page table entries */ > + if (args->start_ptep) { > + pte_free(args->mm, args->start_ptep); > + mm_dec_nr_ptes(args->mm); > + } > + > + if (args->start_pmdp) { > + pmd_free(args->mm, args->start_pmdp); > + mm_dec_nr_pmds(args->mm); > + } > + > + if (args->start_pudp) { > + pud_free(args->mm, args->start_pudp); > + mm_dec_nr_puds(args->mm); > + } > + > + if (args->start_p4dp) > + p4d_free(args->mm, args->p4dp); ^^^^ s/args->p4dp/args->start_p4dp ?