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=-12.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 55D29C35267 for ; Fri, 9 Oct 2020 19:54:40 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 05ADD22CBE for ; Fri, 9 Oct 2020 19:54:39 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 05ADD22CBE Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 3B60C6B011F; Fri, 9 Oct 2020 15:54:14 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 2BCBF6B011D; Fri, 9 Oct 2020 15:54:14 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 136796B011E; Fri, 9 Oct 2020 15:54:14 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0182.hostedemail.com [216.40.44.182]) by kanga.kvack.org (Postfix) with ESMTP id D14636B011B for ; Fri, 9 Oct 2020 15:54:13 -0400 (EDT) Received: from smtpin28.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id 864F6180AD80F for ; Fri, 9 Oct 2020 19:54:13 +0000 (UTC) X-FDA: 77353438386.28.meal97_5212cc1271e3 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin28.hostedemail.com (Postfix) with ESMTP id 6064F6C05; Fri, 9 Oct 2020 19:54:13 +0000 (UTC) X-HE-Tag: meal97_5212cc1271e3 X-Filterd-Recvd-Size: 4921 Received: from mga17.intel.com (mga17.intel.com [192.55.52.151]) by imf30.hostedemail.com (Postfix) with ESMTP; Fri, 9 Oct 2020 19:54:11 +0000 (UTC) IronPort-SDR: kD1R4SWHh3dj22t/18aB109Ebb7yDDpUaLPlHUJgHyckDXjJZvBgAtZ58wAb7JqoLUJXBkx0iN q4TNJCrX68FA== X-IronPort-AV: E=McAfee;i="6000,8403,9769"; a="145397738" X-IronPort-AV: E=Sophos;i="5.77,355,1596524400"; d="scan'208";a="145397738" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by fmsmga107.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 09 Oct 2020 12:54:10 -0700 IronPort-SDR: LoljxrxdEbdUiebRGt6guGtjo6SPfpWGHMJuLgTgYB7BeDU8CJtiGau7DzbQyZ+Y5gpHVnCtT5 urTwCEpflSRg== X-IronPort-AV: E=Sophos;i="5.77,355,1596524400"; d="scan'208";a="343972696" Received: from iweiny-desk2.sc.intel.com (HELO localhost) ([10.3.52.147]) by fmsmga004-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 09 Oct 2020 12:54:09 -0700 From: ira.weiny@intel.com To: Andrew Morton , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Andy Lutomirski , Peter Zijlstra Cc: Ira Weiny , x86@kernel.org, Dave Hansen , Dan Williams , 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, linuxppc-dev@lists.ozlabs.org, kvm@vger.kernel.org, netdev@vger.kernel.org, bpf@vger.kernel.org, kexec@lists.infradead.org, linux-bcache@vger.kernel.org, linux-mtd@lists.infradead.org, devel@driverdev.osuosl.org, linux-efi@vger.kernel.org, linux-mmc@vger.kernel.org, linux-scsi@vger.kernel.org, target-devel@vger.kernel.org, linux-nfs@vger.kernel.org, ceph-devel@vger.kernel.org, linux-ext4@vger.kernel.org, linux-aio@kvack.org, io-uring@vger.kernel.org, linux-erofs@lists.ozlabs.org, linux-um@lists.infradead.org, linux-ntfs-dev@lists.sourceforge.net, reiserfs-devel@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, linux-nilfs@vger.kernel.org, cluster-devel@redhat.com, ecryptfs@vger.kernel.org, linux-cifs@vger.kernel.org, linux-btrfs@vger.kernel.org, linux-afs@lists.infradead.org, linux-rdma@vger.kernel.org, amd-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, intel-gfx@lists.freedesktop.org, drbd-dev@lists.linbit.com, linux-block@vger.kernel.org, xen-devel@lists.xenproject.org, linux-cachefs@redhat.com, samba-technical@lists.samba.org, intel-wired-lan@lists.osuosl.org Subject: [PATCH RFC PKS/PMEM 58/58] [dax|pmem]: Enable stray access protection Date: Fri, 9 Oct 2020 12:50:33 -0700 Message-Id: <20201009195033.3208459-59-ira.weiny@intel.com> X-Mailer: git-send-email 2.28.0.rc0.12.gb6a658bd00c9 In-Reply-To: <20201009195033.3208459-1-ira.weiny@intel.com> References: <20201009195033.3208459-1-ira.weiny@intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable 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: 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. While stray writes are more serious than reads, protection is also enabled for reads. This helps to detect bugs in code which would incorrectly access device memory and prevents a more serious machine checks should those bug reads from a poison page. Enable stray access protection by setting the flag in pgmap which requests it. There is no option presented to the user. 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 1e89513f3c59..e6fb35b4f0fb 100644 --- a/drivers/dax/device.c +++ b/drivers/dax/device.c @@ -430,6 +430,8 @@ int dev_dax_probe(struct device *dev) } =20 dev_dax->pgmap.type =3D MEMORY_DEVICE_GENERIC; + dev_dax->pgmap.flags |=3D PGMAP_PROT_ENABLED; + addr =3D 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 e4dc1ae990fc..9fcd8338e23f 100644 --- a/drivers/nvdimm/pmem.c +++ b/drivers/nvdimm/pmem.c @@ -426,6 +426,8 @@ static int pmem_attach_disk(struct device *dev, return -EBUSY; } =20 + pmem->pgmap.flags |=3D PGMAP_PROT_ENABLED; + q =3D blk_alloc_queue(dev_to_node(dev)); if (!q) return -ENOMEM; --=20 2.28.0.rc0.12.gb6a658bd00c9