From patchwork Mon Jul 19 05:41:38 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Gavin Shan X-Patchwork-Id: 12384735 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,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 E3A80C636CB for ; Mon, 19 Jul 2021 05:42:16 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 9A1D9610A5 for ; Mon, 19 Jul 2021 05:42:16 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9A1D9610A5 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 4230B8D0101; Mon, 19 Jul 2021 01:42:17 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 3FBBE8D0100; Mon, 19 Jul 2021 01:42:17 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 24DD58D0101; Mon, 19 Jul 2021 01:42:17 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0101.hostedemail.com [216.40.44.101]) by kanga.kvack.org (Postfix) with ESMTP id 008C78D0100 for ; Mon, 19 Jul 2021 01:42:16 -0400 (EDT) Received: from smtpin24.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id 94A1D23E51 for ; Mon, 19 Jul 2021 05:42:15 +0000 (UTC) X-FDA: 78378241830.24.2FADA93 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [216.205.24.124]) by imf10.hostedemail.com (Postfix) with ESMTP id 2D66A600199E for ; Mon, 19 Jul 2021 05:42:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1626673334; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=SAAT3twkm8kFqvCnOeL174l1uYZhnlNo8Vm+dCqjiME=; b=hN5ORNmlHYUH792X34opVMr7y6eAcLiPugcEvPVOtNaacGgZx+UHvfFsmghtjyRvmsi196 hI7fB/UPEQEqz+FaabjSxQi4mqI+JVrz5dx0U24m0WQxAtoj4JgnKHcOxwSQbIIpjF7kZa Uuna2noJd9VXALZX4PLeYXGSy94TB44= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-479-0ZvH-gkJMh2En1xhjQaBYg-1; Mon, 19 Jul 2021 01:42:11 -0400 X-MC-Unique: 0ZvH-gkJMh2En1xhjQaBYg-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 8A77C362F8; Mon, 19 Jul 2021 05:42:09 +0000 (UTC) Received: from gshan.redhat.com (vpn2-54-195.bne.redhat.com [10.64.54.195]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 50BB2369A; Mon, 19 Jul 2021 05:42:06 +0000 (UTC) From: Gavin Shan To: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org, anshuman.khandual@arm.com, catalin.marinas@arm.com, will@kernel.org, akpm@linux-foundation.org, chuhu@redhat.com, shan.gavin@gmail.com Subject: [PATCH v2 12/12] mm/debug_vm_pgtable: Fix corrupted page flag Date: Mon, 19 Jul 2021 13:41:38 +0800 Message-Id: <20210719054138.198373-13-gshan@redhat.com> In-Reply-To: <20210719054138.198373-1-gshan@redhat.com> References: <20210719054138.198373-1-gshan@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 Authentication-Results: imf10.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b=hN5ORNml; spf=none (imf10.hostedemail.com: domain of gshan@redhat.com has no SPF policy when checking 216.205.24.124) smtp.mailfrom=gshan@redhat.com; dmarc=pass (policy=none) header.from=redhat.com X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: 2D66A600199E X-Stat-Signature: 8pged5dejtd8scqsjh4wbtm8yd5s3ort X-HE-Tag: 1626673335-911700 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: In page table entry modifying tests, set_xxx_at() are used to populate the page table entries. On ARM64, PG_arch_1 is set to the target page flag if execution permission is given. The page flag is kept when the page is free'd to buddy's free area list. However, it will trigger page checking failure when it's pulled from the buddy's free area list, as the following warning messages indicate. BUG: Bad page state in process memhog pfn:08000 page:0000000015c0a628 refcount:0 mapcount:0 \ mapping:0000000000000000 index:0x1 pfn:0x8000 flags: 0x7ffff8000000800(arch_1|node=0|zone=0|lastcpupid=0xfffff) raw: 07ffff8000000800 dead000000000100 dead000000000122 0000000000000000 raw: 0000000000000001 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: PAGE_FLAGS_CHECK_AT_PREP flag(s) set This fixes the issue by clearing PG_arch_1 through flush_dcache_page() after set_xxx_at() is called. Signed-off-by: Gavin Shan --- mm/debug_vm_pgtable.c | 32 ++++++++++++++++++++++++++++---- 1 file changed, 28 insertions(+), 4 deletions(-) diff --git a/mm/debug_vm_pgtable.c b/mm/debug_vm_pgtable.c index 162a12c10aa8..926d5a78f8c7 100644 --- a/mm/debug_vm_pgtable.c +++ b/mm/debug_vm_pgtable.c @@ -29,6 +29,8 @@ #include #include #include + +#include #include #include @@ -118,6 +120,7 @@ static void __init pte_basic_tests(struct pgtable_debug_args *args, int idx) static void __init pte_advanced_tests(struct pgtable_debug_args *args) { + struct page *page; pte_t pte; /* @@ -127,13 +130,16 @@ static void __init pte_advanced_tests(struct pgtable_debug_args *args) */ pr_debug("Validating PTE advanced\n"); - if (args->pte_pfn == ULONG_MAX) { + page = (args->pte_pfn != ULONG_MAX) ? + pfn_to_page(args->pte_pfn) : NULL; + if (!page) { pr_debug("%s: Skipped\n", __func__); return; } pte = pfn_pte(args->pte_pfn, args->page_prot); set_pte_at(args->mm, args->vaddr, args->ptep, pte); + flush_dcache_page(page); ptep_set_wrprotect(args->mm, args->vaddr, args->ptep); pte = ptep_get(args->ptep); WARN_ON(pte_write(pte)); @@ -145,6 +151,7 @@ static void __init pte_advanced_tests(struct pgtable_debug_args *args) pte = pte_wrprotect(pte); pte = pte_mkclean(pte); set_pte_at(args->mm, args->vaddr, args->ptep, pte); + flush_dcache_page(page); pte = pte_mkwrite(pte); pte = pte_mkdirty(pte); ptep_set_access_flags(args->vma, args->vaddr, args->ptep, pte, 1); @@ -157,6 +164,7 @@ static void __init pte_advanced_tests(struct pgtable_debug_args *args) pte = pfn_pte(args->pte_pfn, args->page_prot); pte = pte_mkyoung(pte); set_pte_at(args->mm, args->vaddr, args->ptep, pte); + flush_dcache_page(page); ptep_test_and_clear_young(args->vma, args->vaddr, args->ptep); pte = ptep_get(args->ptep); WARN_ON(pte_young(pte)); @@ -215,6 +223,7 @@ static void __init pmd_basic_tests(struct pgtable_debug_args *args, int idx) static void __init pmd_advanced_tests(struct pgtable_debug_args *args) { + struct page *page; pmd_t pmd; unsigned long vaddr = (args->vaddr & HPAGE_PMD_MASK); @@ -222,7 +231,9 @@ static void __init pmd_advanced_tests(struct pgtable_debug_args *args) return; pr_debug("Validating PMD advanced\n"); - if (args->pmd_pfn == ULONG_MAX) { + page = (args->pmd_pfn != ULONG_MAX) ? + pfn_to_page(args->pmd_pfn) : NULL; + if (!page) { pr_debug("%s: Skipped\n", __func__); return; } @@ -231,6 +242,7 @@ static void __init pmd_advanced_tests(struct pgtable_debug_args *args) pmd = pfn_pmd(args->pmd_pfn, args->page_prot); set_pmd_at(args->mm, vaddr, args->pmdp, pmd); + flush_dcache_page(page); pmdp_set_wrprotect(args->mm, vaddr, args->pmdp); pmd = READ_ONCE(*(args->pmdp)); WARN_ON(pmd_write(pmd)); @@ -242,6 +254,7 @@ static void __init pmd_advanced_tests(struct pgtable_debug_args *args) pmd = pmd_wrprotect(pmd); pmd = pmd_mkclean(pmd); set_pmd_at(args->mm, vaddr, args->pmdp, pmd); + flush_dcache_page(page); pmd = pmd_mkwrite(pmd); pmd = pmd_mkdirty(pmd); pmdp_set_access_flags(args->vma, vaddr, args->pmdp, pmd, 1); @@ -254,6 +267,7 @@ static void __init pmd_advanced_tests(struct pgtable_debug_args *args) pmd = pmd_mkhuge(pfn_pmd(args->pmd_pfn, args->page_prot)); pmd = pmd_mkyoung(pmd); set_pmd_at(args->mm, vaddr, args->pmdp, pmd); + flush_dcache_page(page); pmdp_test_and_clear_young(args->vma, vaddr, args->pmdp); pmd = READ_ONCE(*(args->pmdp)); WARN_ON(pmd_young(pmd)); @@ -340,6 +354,7 @@ static void __init pud_basic_tests(struct pgtable_debug_args *args, int idx) static void __init pud_advanced_tests(struct pgtable_debug_args *args) { + struct page *page; unsigned long vaddr = (args->vaddr & HPAGE_PUD_MASK); pud_t pud; @@ -347,13 +362,16 @@ static void __init pud_advanced_tests(struct pgtable_debug_args *args) return; pr_debug("Validating PUD advanced\n"); - if (args->pud_pfn == ULONG_MAX) { + page = (args->pud_pfn != ULONG_MAX) ? + pfn_to_page(args->pud_pfn) : NULL; + if (!page) { pr_debug("%s: Skipped\n", __func__); return; } pud = pfn_pud(args->pud_pfn, args->page_prot); set_pud_at(args->mm, vaddr, args->pudp, pud); + flush_dcache_page(page); pudp_set_wrprotect(args->mm, vaddr, args->pudp); pud = READ_ONCE(*(args->pudp)); WARN_ON(pud_write(pud)); @@ -367,6 +385,7 @@ static void __init pud_advanced_tests(struct pgtable_debug_args *args) pud = pud_wrprotect(pud); pud = pud_mkclean(pud); set_pud_at(args->mm, vaddr, args->pudp, pud); + flush_dcache_page(page); pud = pud_mkwrite(pud); pud = pud_mkdirty(pud); pudp_set_access_flags(args->vma, vaddr, args->pudp, pud, 1); @@ -382,6 +401,7 @@ static void __init pud_advanced_tests(struct pgtable_debug_args *args) pud = pfn_pud(args->pud_pfn, args->page_prot); pud = pud_mkyoung(pud); set_pud_at(args->mm, vaddr, args->pudp, pud); + flush_dcache_page(page); pudp_test_and_clear_young(args->vma, vaddr, args->pudp); pud = READ_ONCE(*(args->pudp)); WARN_ON(pud_young(pud)); @@ -595,10 +615,13 @@ static void __init pgd_populate_tests(struct pgtable_debug_args *args) { } static void __init pte_clear_tests(struct pgtable_debug_args *args) { + struct page *page; pte_t pte; pr_debug("Validating PTE clear\n"); - if (args->pte_pfn == ULONG_MAX) { + page = (args->pte_pfn != ULONG_MAX) ? + pfn_to_page(args->pte_pfn) : NULL; + if (!page) { pr_debug("%s: Skipped\n", __func__); return; } @@ -608,6 +631,7 @@ static void __init pte_clear_tests(struct pgtable_debug_args *args) pte = __pte(pte_val(pte) | RANDOM_ORVALUE); #endif set_pte_at(args->mm, args->vaddr, args->ptep, pte); + flush_dcache_page(page); barrier(); pte_clear(args->mm, args->vaddr, args->ptep); pte = ptep_get(args->ptep);