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=-13.0 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 57147C433E0 for ; Tue, 14 Jul 2020 07:04:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3B38A22225 for ; Tue, 14 Jul 2020 07:04:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727105AbgGNHEj (ORCPT ); Tue, 14 Jul 2020 03:04:39 -0400 Received: from mga04.intel.com ([192.55.52.120]:50389 "EHLO mga04.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727034AbgGNHEb (ORCPT ); Tue, 14 Jul 2020 03:04:31 -0400 IronPort-SDR: ich8xV8hFnmzCz3xenXCt5Gwp+Pu22XqcldrFpG6x50tDs0YTP3pCyVSc5MvlINldsLKGEd0I+ MNn2n1F8J6TA== X-IronPort-AV: E=McAfee;i="6000,8403,9681"; a="146304368" X-IronPort-AV: E=Sophos;i="5.75,350,1589266800"; d="scan'208";a="146304368" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga005.jf.intel.com ([10.7.209.41]) by fmsmga104.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 Jul 2020 00:04:30 -0700 IronPort-SDR: OlctpnIJwdlGQxS+Bsa4EvBdFZhgaMgi6E93HtogmUqsYd+MIKqgpv8ZX2Fg+6KeQMAbeYu29A wm1rPhIk0yOg== X-IronPort-AV: E=Sophos;i="5.75,350,1589266800"; d="scan'208";a="459583558" Received: from iweiny-desk2.sc.intel.com (HELO localhost) ([10.3.52.147]) by orsmga005-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 Jul 2020 00:04:29 -0700 From: ira.weiny@intel.com To: Thomas Gleixner , Ingo Molnar , Borislav Petkov , Andy Lutomirski , Peter Zijlstra Cc: Ira Weiny , x86@kernel.org, Dave Hansen , Dan Williams , Vishal Verma , Andrew Morton , Fenghua Yu , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-nvdimm@lists.01.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-kselftest@vger.kernel.org Subject: [RFC PATCH 15/15] [dax|pmem]: Enable stray write protection Date: Tue, 14 Jul 2020 00:02:20 -0700 Message-Id: <20200714070220.3500839-16-ira.weiny@intel.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200714070220.3500839-1-ira.weiny@intel.com> References: <20200714070220.3500839-1-ira.weiny@intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Ira Weiny Protecting against stray writes is particularly important for PMEM because, unlike writes to anonymous memory, writes to PMEM persists across a reboot. Thus data corruption could result in permanent loss of data. Therefore, there is no option presented to the user. Enable stray write protection by setting the flag in pgmap which requests it. Note if Zone Device Access Protection not be supported this flag will have no affect. Signed-off-by: Ira Weiny --- drivers/dax/device.c | 2 ++ drivers/nvdimm/pmem.c | 2 ++ 2 files changed, 4 insertions(+) diff --git a/drivers/dax/device.c b/drivers/dax/device.c index 4c0af2eb7e19..884f66d73d32 100644 --- a/drivers/dax/device.c +++ b/drivers/dax/device.c @@ -430,6 +430,8 @@ int dev_dax_probe(struct device *dev) } dev_dax->pgmap.type = MEMORY_DEVICE_DEVDAX; + dev_dax->pgmap.flags |= PGMAP_PROT_ENABLED; + addr = devm_memremap_pages(dev, &dev_dax->pgmap); if (IS_ERR(addr)) return PTR_ERR(addr); diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c index 46c11a09b813..9416a660eede 100644 --- a/drivers/nvdimm/pmem.c +++ b/drivers/nvdimm/pmem.c @@ -427,6 +427,8 @@ static int pmem_attach_disk(struct device *dev, return -EBUSY; } + pmem->pgmap.flags |= PGMAP_PROT_ENABLED; + q = blk_alloc_queue(pmem_make_request, dev_to_node(dev)); if (!q) return -ENOMEM; -- 2.25.1