From patchwork Wed Apr 3 14:16:26 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Steven Price X-Patchwork-Id: 10883933 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 477B717E1 for ; Wed, 3 Apr 2019 14:18:30 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 30FAA288EF for ; Wed, 3 Apr 2019 14:18:30 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 2592828A1B; Wed, 3 Apr 2019 14:18:30 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_NONE autolearn=ham version=3.3.1 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 82743288EF for ; Wed, 3 Apr 2019 14:18:29 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 683626B0280; Wed, 3 Apr 2019 10:18:27 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id 632E06B0281; Wed, 3 Apr 2019 10:18:27 -0400 (EDT) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 4FB9C6B0282; Wed, 3 Apr 2019 10:18:27 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from mail-ed1-f70.google.com (mail-ed1-f70.google.com [209.85.208.70]) by kanga.kvack.org (Postfix) with ESMTP id 0521D6B0280 for ; Wed, 3 Apr 2019 10:18:27 -0400 (EDT) Received: by mail-ed1-f70.google.com with SMTP id n12so7651110edo.5 for ; Wed, 03 Apr 2019 07:18:26 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-original-authentication-results:x-gm-message-state:from:to:cc :subject:date:message-id:in-reply-to:references:mime-version :content-transfer-encoding; bh=0Qu5DM7t7O6eLZ930vwdwyGGSyJREtb45OisMEetzTk=; b=a+LDXYywEoYdECjpsag9Qt4laP7e7zq7kQ2wUEDXGuyKyWX8Pu/4tjhPeHaK1fjVO7 WLXnrYTFfkZ4Bzr5GSrLF2Y9SIv0tPCvXLIin21r5/ChYWWeR6ygjLp9G8m2JsRnJI2u EORmafHexFFEibb3hiWQtjcaDPVMteT+S9DQFyAJXd4X3vwr13d40gnX+nSuSgf6uKdr 4XO3ZinO63SRgujmH5MeRtsCaptjWfqq+Zv96+CKSDadZv5vuve53vRyS3aDwvdf/C1h 1Gco15cCGV49ZpIMBpK/LxcBBYZsbaxh3yvvb61StqNCKM0y1XUPqkDsFzZvxIEFP5Dy j/hw== X-Original-Authentication-Results: mx.google.com; spf=pass (google.com: domain of steven.price@arm.com designates 217.140.101.70 as permitted sender) smtp.mailfrom=steven.price@arm.com X-Gm-Message-State: APjAAAWAqbNSptwurKAITv5BPPUloyuWAQQ8n/FNdivdQhhZk2SInpqT Rw/1uW4FyLwJUAIzZHni+4mXXbRedX5LjNuISBf0nfgC/y8EuIQHgXMaX9GLCl8IqLtVbkHFJqJ +UZEZnCfYrDxe28sfUULJznUGJAbrnE+DWiv82/mM67INIAwioyKFBkNAf4u+QsrtDg== X-Received: by 2002:a50:ec89:: with SMTP id e9mr31934559edr.252.1554301106543; Wed, 03 Apr 2019 07:18:26 -0700 (PDT) X-Google-Smtp-Source: APXvYqwU1kJo7gGld2UhuMwibGXOAqu3CzYF9oSuTWaov/ACL4kyTxyiDsZ+OguLoyswC11gDWnw X-Received: by 2002:a50:ec89:: with SMTP id e9mr31934508edr.252.1554301105640; Wed, 03 Apr 2019 07:18:25 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1554301105; cv=none; d=google.com; s=arc-20160816; b=M5YSDSnKRtT8LbJBNy+F9ZEA+EzLS7TdtyUIHTAoP1JfAsdSxRLplgxzRzz0bM4Mcw aPEMhsxLl8YmWybaUXMx9TJa3VCklm2PHwlQJdioC8ElcTavzKVW4CQ9+0R3xj+Jep4V U7CAcBhf7Ds61+DxW5EjM1SruH4V08FSYc9uO1DGh6w+C6FomMhN0Pqs3X2QUm87ts3D gHjxTnXK82UGaunrRqAaAHKCW/ySWRzfpAWLCJ7iz5cMrJJ7L/LY8jT6dfFOwH73+zrE 4t526LZidy/eFy80i0OyIQr24YKVzgN3iwXLSWWELp+2DL86t3xM3dBsyaahohZ9N3si 2e+g== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from; bh=0Qu5DM7t7O6eLZ930vwdwyGGSyJREtb45OisMEetzTk=; b=fDjVR6gTdoyZHG6vq274Q5bkq1LLVJFephExXlaMfDBryKZEKwN3P3PF9seR4EKI+j tZYw6qTfR+qsvW0dgBEPw0bx/x/2L7/hzmUDlS+D/v9SATBuOrgv5nTBeOtbheuJeGSB DVYtHBH3EO8GQ8zE5q8dcAXsnf5Nwr+Ox0ojCOhvxIGdon9oG88Yy4g6wjYM3P5zVmcF 7ir4oEfv8ZoiuUv7sQI/HyXRjs7iXUFfr9WsYFduXnIl0pwbfXjlvaADn26QJ5W8MlMA avShZCFc0IF2MQcz+cBofV1T9YywfJY/Yt6czZP7YZ/29lhZ0LRDyMwFn5wtb7O95Z3k UUyA== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of steven.price@arm.com designates 217.140.101.70 as permitted sender) smtp.mailfrom=steven.price@arm.com Received: from foss.arm.com (usa-sjc-mx-foss1.foss.arm.com. [217.140.101.70]) by mx.google.com with ESMTP id w48si2420346edc.295.2019.04.03.07.18.25 for ; Wed, 03 Apr 2019 07:18:25 -0700 (PDT) Received-SPF: pass (google.com: domain of steven.price@arm.com designates 217.140.101.70 as permitted sender) client-ip=217.140.101.70; Authentication-Results: mx.google.com; spf=pass (google.com: domain of steven.price@arm.com designates 217.140.101.70 as permitted sender) smtp.mailfrom=steven.price@arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 8FB1D168F; Wed, 3 Apr 2019 07:18:24 -0700 (PDT) Received: from e112269-lin.arm.com (e112269-lin.cambridge.arm.com [10.1.196.69]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 2C9A03F68F; Wed, 3 Apr 2019 07:18:21 -0700 (PDT) From: Steven Price To: linux-mm@kvack.org Cc: Steven Price , Andy Lutomirski , Ard Biesheuvel , Arnd Bergmann , Borislav Petkov , Catalin Marinas , Dave Hansen , Ingo Molnar , James Morse , =?utf-8?b?SsOpcsO0bWUgR2xpc3Nl?= , Peter Zijlstra , Thomas Gleixner , Will Deacon , x86@kernel.org, "H. Peter Anvin" , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Mark Rutland , "Liang, Kan" , Andrew Morton Subject: [PATCH v8 19/20] x86: mm: Convert ptdump_walk_pgd_level_core() to take an mm_struct Date: Wed, 3 Apr 2019 15:16:26 +0100 Message-Id: <20190403141627.11664-20-steven.price@arm.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190403141627.11664-1-steven.price@arm.com> References: <20190403141627.11664-1-steven.price@arm.com> MIME-Version: 1.0 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: X-Virus-Scanned: ClamAV using ClamSMTP An mm_struct is needed to enable x86 to use of the generic walk_page_range() function. In the case of walking the user page tables (when CONFIG_PAGE_TABLE_ISOLATION is enabled), it is necessary to create a fake_mm structure because there isn't an mm_struct with a pointer to the pgd of the user page tables. This fake_mm structure is initialised with the minimum necessary for the generic page walk code. Signed-off-by: Steven Price --- arch/x86/mm/dump_pagetables.c | 36 ++++++++++++++++++++--------------- 1 file changed, 21 insertions(+), 15 deletions(-) diff --git a/arch/x86/mm/dump_pagetables.c b/arch/x86/mm/dump_pagetables.c index 40b3f1da6e15..c0fbb9e5a790 100644 --- a/arch/x86/mm/dump_pagetables.c +++ b/arch/x86/mm/dump_pagetables.c @@ -111,8 +111,6 @@ static struct addr_marker address_markers[] = { [END_OF_SPACE_NR] = { -1, NULL } }; -#define INIT_PGD ((pgd_t *) &init_top_pgt) - #else /* CONFIG_X86_64 */ enum address_markers_idx { @@ -147,8 +145,6 @@ static struct addr_marker address_markers[] = { [END_OF_SPACE_NR] = { -1, NULL } }; -#define INIT_PGD (swapper_pg_dir) - #endif /* !CONFIG_X86_64 */ /* Multipliers for offsets within the PTEs */ @@ -522,10 +518,10 @@ static inline bool is_hypervisor_range(int idx) #endif } -static void ptdump_walk_pgd_level_core(struct seq_file *m, pgd_t *pgd, +static void ptdump_walk_pgd_level_core(struct seq_file *m, struct mm_struct *mm, bool checkwx, bool dmesg) { - pgd_t *start = pgd; + pgd_t *start = mm->pgd; pgprotval_t prot, eff; int i; struct pg_state st = {}; @@ -572,39 +568,49 @@ static void ptdump_walk_pgd_level_core(struct seq_file *m, pgd_t *pgd, void ptdump_walk_pgd_level(struct seq_file *m, struct mm_struct *mm) { - ptdump_walk_pgd_level_core(m, mm->pgd, false, true); + ptdump_walk_pgd_level_core(m, mm, false, true); } +#ifdef CONFIG_PAGE_TABLE_ISOLATION +static void ptdump_walk_pgd_level_user_core(struct seq_file *m, + struct mm_struct *mm, + bool checkwx, bool dmesg) +{ + struct mm_struct fake_mm = { + .pgd = kernel_to_user_pgdp(mm->pgd) + }; + init_rwsem(&fake_mm.mmap_sem); + ptdump_walk_pgd_level_core(m, &fake_mm, checkwx, dmesg); +} +#endif + void ptdump_walk_pgd_level_debugfs(struct seq_file *m, struct mm_struct *mm, bool user) { - pgd_t *pgd = mm->pgd; #ifdef CONFIG_PAGE_TABLE_ISOLATION if (user && static_cpu_has(X86_FEATURE_PTI)) - pgd = kernel_to_user_pgdp(pgd); + ptdump_walk_pgd_level_user_core(m, mm, false, false); + else #endif - ptdump_walk_pgd_level_core(m, pgd, false, false); + ptdump_walk_pgd_level_core(m, mm, false, false); } EXPORT_SYMBOL_GPL(ptdump_walk_pgd_level_debugfs); void ptdump_walk_user_pgd_level_checkwx(void) { #ifdef CONFIG_PAGE_TABLE_ISOLATION - pgd_t *pgd = INIT_PGD; - if (!(__supported_pte_mask & _PAGE_NX) || !static_cpu_has(X86_FEATURE_PTI)) return; pr_info("x86/mm: Checking user space page tables\n"); - pgd = kernel_to_user_pgdp(pgd); - ptdump_walk_pgd_level_core(NULL, pgd, true, false); + ptdump_walk_pgd_level_user_core(NULL, &init_mm, true, false); #endif } void ptdump_walk_pgd_level_checkwx(void) { - ptdump_walk_pgd_level_core(NULL, INIT_PGD, true, false); + ptdump_walk_pgd_level_core(NULL, &init_mm, true, false); } static int __init pt_dump_init(void)