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,URIBL_BLOCKED,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 E30E2C43470 for ; Tue, 14 Jul 2020 07:04:38 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id B122C221ED for ; Tue, 14 Jul 2020 07:04:38 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B122C221ED 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 234398D0010; Tue, 14 Jul 2020 03:04:31 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 1BFEC8D000A; Tue, 14 Jul 2020 03:04:31 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 061828D0010; Tue, 14 Jul 2020 03:04:31 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0092.hostedemail.com [216.40.44.92]) by kanga.kvack.org (Postfix) with ESMTP id E2A178D000A for ; Tue, 14 Jul 2020 03:04:30 -0400 (EDT) Received: from smtpin09.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id ADA522DFC for ; Tue, 14 Jul 2020 07:04:30 +0000 (UTC) X-FDA: 77035793100.09.road76_03158a426eef Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin09.hostedemail.com (Postfix) with ESMTP id 7C1E0180AD804 for ; Tue, 14 Jul 2020 07:04:30 +0000 (UTC) X-HE-Tag: road76_03158a426eef X-Filterd-Recvd-Size: 3458 Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) by imf30.hostedemail.com (Postfix) with ESMTP for ; Tue, 14 Jul 2020 07:04:29 +0000 (UTC) IronPort-SDR: BITHgR6JTVzGiH/M/3CirV1usoW/UN0V05KpLGgQ8Ps3bMzh/J69Y05BfJYPYmEu+/AGanmUVV 5GfZDZc/5eKQ== X-IronPort-AV: E=McAfee;i="6000,8403,9681"; a="136970774" X-IronPort-AV: E=Sophos;i="5.75,350,1589266800"; d="scan'208";a="136970774" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by orsmga101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 Jul 2020 00:04:28 -0700 IronPort-SDR: 2GlF4QiJnNhoGgMJ5XMp7xdyQ0iPfyqW+HUR8m12RTg7zWuuTG19TEkAYr8cw+FwjIa2w1Dc3M MV33WpvpzAfw== X-IronPort-AV: E=Sophos;i="5.75,350,1589266800"; d="scan'208";a="269934896" Received: from iweiny-desk2.sc.intel.com (HELO localhost) ([10.3.52.147]) by fmsmga008-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 Jul 2020 00:04:28 -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 14/15] nvdimm/pmem: Stray write protection for pmem->virt_addr Date: Tue, 14 Jul 2020 00:02:19 -0700 Message-Id: <20200714070220.3500839-15-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 X-Rspamd-Queue-Id: 7C1E0180AD804 X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam05 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 The pmem driver uses a cached virtual address to access its memory directly. Because the nvdimm driver is well aware of the special protections it has mapped memory with, we call dev_access_[en|dis]able() around the direct pmem->virt_addr (pmem_addr) usage instead of the unnecessary overhead of trying to get a page to kmap. Signed-off-by: Ira Weiny --- drivers/nvdimm/pmem.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c index d25e66fd942d..46c11a09b813 100644 --- a/drivers/nvdimm/pmem.c +++ b/drivers/nvdimm/pmem.c @@ -148,7 +148,9 @@ static blk_status_t pmem_do_read(struct pmem_device *= pmem, if (unlikely(is_bad_pmem(&pmem->bb, sector, len))) return BLK_STS_IOERR; =20 + dev_access_enable(); rc =3D read_pmem(page, page_off, pmem_addr, len); + dev_access_disable(); flush_dcache_page(page); return rc; } @@ -180,11 +182,13 @@ static blk_status_t pmem_do_write(struct pmem_devic= e *pmem, * after clear poison. */ flush_dcache_page(page); + dev_access_enable(); write_pmem(pmem_addr, page, page_off, len); if (unlikely(bad_pmem)) { rc =3D pmem_clear_poison(pmem, pmem_off, len); write_pmem(pmem_addr, page, page_off, len); } + dev_access_disable(); =20 return rc; } --=20 2.25.1