From patchwork Mon Aug 2 06:04:07 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Gavin Shan X-Patchwork-Id: 12413323 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=-8.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,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 E355EC4338F for ; Mon, 2 Aug 2021 06:04:46 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 7023860F9F for ; Mon, 2 Aug 2021 06:04:46 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 7023860F9F Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvack.org Received: by kanga.kvack.org (Postfix) id 80B306B0033; Mon, 2 Aug 2021 02:04:45 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 7BBF56B0036; Mon, 2 Aug 2021 02:04:45 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 6A9556B005D; Mon, 2 Aug 2021 02:04:45 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0213.hostedemail.com [216.40.44.213]) by kanga.kvack.org (Postfix) with ESMTP id 4CFCE6B0033 for ; Mon, 2 Aug 2021 02:04:45 -0400 (EDT) Received: from smtpin10.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 00661181AC1F5 for ; Mon, 2 Aug 2021 06:04:44 +0000 (UTC) X-FDA: 78429101730.10.8339AD8 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by imf10.hostedemail.com (Postfix) with ESMTP id 9492C60022DB for ; Mon, 2 Aug 2021 06:04:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1627884284; 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; bh=iLC4bwfdSbwF0yo5Y8i+abm/lowpqvGEJGzZXdiM5N0=; b=SQtfn2qzQspmrD9XfAu0TWb4NmInoPJVODScwRKxmHGPlhOJB+2maYe2A+tuySqC5sauXM 8so2qUDiVk+eZ9Y87pGQZ0o3c8z0tr6ykzLcb1MdTKiSH1X9bFAbNxpR6YrA11AuWL4tCF OzeZIkVEHyxixvGFPKbRtlPdB60NwHo= 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-296-U5vS8WJCNpuEXxe4K_SxXQ-1; Mon, 02 Aug 2021 02:04:42 -0400 X-MC-Unique: U5vS8WJCNpuEXxe4K_SxXQ-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id A10DD185302A; Mon, 2 Aug 2021 06:04:40 +0000 (UTC) Received: from gshan.redhat.com (vpn2-54-184.bne.redhat.com [10.64.54.184]) by smtp.corp.redhat.com (Postfix) with ESMTPS id B3BCF1ABD8; Mon, 2 Aug 2021 06:04:35 +0000 (UTC) From: Gavin Shan To: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org, anshuman.khandual@arm.com, gerald.schaefer@linux.ibm.com, aneesh.kumar@linux.ibm.com, christophe.leroy@csgroup.eu, cai@lca.pw, catalin.marinas@arm.com, will@kernel.org, vgupta@synopsys.com, akpm@linux-foundation.org, chuhu@redhat.com, shan.gavin@gmail.com Subject: [PATCH v5 00/12] mm/debug_vm_pgtable: Enhancements Date: Mon, 2 Aug 2021 14:04:07 +0800 Message-Id: <20210802060419.1360913-1-gshan@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 9492C60022DB Authentication-Results: imf10.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b=SQtfn2qz; dmarc=pass (policy=none) header.from=redhat.com; spf=none (imf10.hostedemail.com: domain of gshan@redhat.com has no SPF policy when checking 170.10.133.124) smtp.mailfrom=gshan@redhat.com X-Stat-Signature: pef53sebthz8x6wqx68g7hfog3a4jicz X-HE-Tag: 1627884284-81355 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: There are couple of issues with current implementations and this series tries to resolve the issues: (a) All needed information are scattered in variables, passed to various test functions. The code is organized in pretty much relaxed fashion. (b) The page isn't allocated from buddy during page table entry modifying tests. The page can be invalid, conflicting to the implementations of set_xxx_at() on ARM64. The target page is accessed so that the iCache can be flushed when execution permission is given on ARM64. Besides, the target page can be unmapped and accessing to it causes kernel crash. "struct pgtable_debug_args" is introduced to address issue (a). For issue (b), the used page is allocated from buddy in page table entry modifying tests. The corresponding tets will be skipped if we fail to allocate the (huge) page. For other test cases, the original page around to kernel symbol (@start_kernel) is still used. The patches are organized as below. PATCH[2-10] could be combined to one patch, but it will make the review harder: PATCH[1] introduces "struct pgtable_debug_args" as place holder of all needed information. With it, the old and new implementation can coexist. PATCH[2-10] uses "struct pgtable_debug_args" in various test functions. PATCH[11] removes the unused code for old implementation. PATCH[12] fixes the issue of corrupted page flag for ARM64 Changelog ========= v5: * Pick r-bs from Anshuman and rebase to 5.14.rc4 (Gavin) * Use args->start_p4dp to free p4d entries (Anshuman) * Introduce helper to allocate huge page in init_arg() (Anshuman) * Bail early if the allocated page doesn't exist in swap_migration_tests() and correct the comments (Anshuman) * Add fixes tag to PATCH[v4 12/12] (Christophe) * Address misc comments (Anshuman) v4: * Determine the page allocation method according to MAX_ORDER (Anshuman) * Move existing comments to init_args() (Anshuman) * Code refactoring as suggested by Anshuman (Anshuman) * Improved commit log and add comments for flush_dcache_page() in PATCH[v4 12/12] (Anshuman) * Address misc comments (Anshuman) v3: * Fix the warning caused by allocating more pages than (1 << (MAX_ORDER - 1)) in init_args() (syzbot) * Fix build warning by dropping unused variables in separate patches (0-day) * Missed "WARN_ON(!pud_none(pud))" in pud_huge_tests() in PATCH[v2 09/12] (0-day) * Fix the subjects for PATCH[05/12] and PATCH[09/12] (Gavin) v2: * Rename struct vm_pgtable_debug to struct pgtable_debug_args. The parameter name to various test functions are renamed to "@args" (Anshuman) * Code changes as suggested by Anshuman (Anshuman) Gavin Shan (12): mm/debug_vm_pgtable: Introduce struct pgtable_debug_args mm/debug_vm_pgtable: Use struct pgtable_debug_args in basic tests mm/debug_vm_pgtable: Use struct pgtable_debug_args in leaf and savewrite tests mm/debug_vm_pgtable: Use struct pgtable_debug_args in protnone and devmap tests mm/debug_vm_pgtable: Use struct pgtable_debug_args in soft_dirty and swap tests mm/debug_vm_pgtable: Use struct pgtable_debug_args in migration and thp tests mm/debug_vm_pgtable: Use struct pgtable_debug_args in PTE modifying tests mm/debug_vm_pgtable: Use struct pgtable_debug_args in PMD modifying tests mm/debug_vm_pgtable: Use struct pgtable_debug_args in PUD modifying tests mm/debug_vm_pgtable: Use struct pgtable_debug_args in PGD and P4D modifying tests mm/debug_vm_pgtable: Remove unused code mm/debug_vm_pgtable: Fix corrupted page flag mm/debug_vm_pgtable.c | 916 +++++++++++++++++++++++++----------------- 1 file changed, 558 insertions(+), 358 deletions(-)