From patchwork Fri Jul 17 07:20:54 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ira Weiny X-Patchwork-Id: 11669549 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id BDA3F13A4 for ; Fri, 17 Jul 2020 08:51:22 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 93214207F5 for ; Fri, 17 Jul 2020 08:51:22 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 93214207F5 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 DB9026B0032; Fri, 17 Jul 2020 04:51:21 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id D405A6B0033; Fri, 17 Jul 2020 04:51:21 -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 C308E6B0036; Fri, 17 Jul 2020 04:51:21 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0115.hostedemail.com [216.40.44.115]) by kanga.kvack.org (Postfix) with ESMTP id ADA936B0032 for ; Fri, 17 Jul 2020 04:51:21 -0400 (EDT) Received: from smtpin28.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id 72664231C3 for ; Fri, 17 Jul 2020 08:51:21 +0000 (UTC) X-FDA: 77046948762.28.wall96_550623426f09 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin28.hostedemail.com (Postfix) with ESMTP id 41BD6231D0 for ; Fri, 17 Jul 2020 08:51:21 +0000 (UTC) X-Spam-Summary: 1,0,0,,d41d8cd98f00b204,ira.weiny@intel.com,,RULES_HIT:30003:30054:30064,0,RBL:192.55.52.136:@intel.com:.lbl8.mailshell.net-64.95.201.95 62.18.0.100;04yfx7xyt1fzn4kzy8fxmcxqn1ztroc1pqsagsjrhxerb1wxuwudzq56gcndk31.pycrftr1dh9u6ok4mhhinnz87du8dia3ner9p4xo8qkw89crz9bg4oop47kt9e8.o-lbl8.mailshell.net-223.238.255.100,CacheIP:none,Bayesian:0.5,0.5,0.5,Netcheck:none,DomainCache:0,MSF:not bulk,SPF:ft,MSBL:0,DNSBL:neutral,Custom_rules:0:0:0,LFtime:25,LUA_SUMMARY:none X-HE-Tag: wall96_550623426f09 X-Filterd-Recvd-Size: 3496 Received: from mga12.intel.com (mga12.intel.com [192.55.52.136]) by imf15.hostedemail.com (Postfix) with ESMTP for ; Fri, 17 Jul 2020 08:51:19 +0000 (UTC) IronPort-SDR: VNLOC7T+MmqhWGObafH5h/rTLYcUQNVGUl1M5NfTBdJ70FAZlly6YPFd3zdnJ3R/ZV7xDSPJMv 10OsypOXjZaw== X-IronPort-AV: E=McAfee;i="6000,8403,9684"; a="129111947" X-IronPort-AV: E=Sophos;i="5.75,362,1589266800"; d="scan'208";a="129111947" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga006.fm.intel.com ([10.253.24.20]) by fmsmga106.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 17 Jul 2020 00:21:09 -0700 IronPort-SDR: DMw9Bg0fto/LYRsYYNO/RmvrHFgQrAU3QdS7dMnjcycrTtADfzCGcIaR6tz+7treV3M3/2IvuB Hz5Snhjs883w== X-IronPort-AV: E=Sophos;i="5.75,362,1589266800"; d="scan'208";a="486385675" Received: from iweiny-desk2.sc.intel.com (HELO localhost) ([10.3.52.147]) by fmsmga006-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 17 Jul 2020 00:21:09 -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: [PATCH RFC V2 15/17] nvdimm/pmem: Stray write protection for pmem->virt_addr Date: Fri, 17 Jul 2020 00:20:54 -0700 Message-Id: <20200717072056.73134-16-ira.weiny@intel.com> X-Mailer: git-send-email 2.28.0.rc0.12.gb6a658bd00c9 In-Reply-To: <20200717072056.73134-1-ira.weiny@intel.com> References: <20200717072056.73134-1-ira.weiny@intel.com> MIME-Version: 1.0 X-Rspamd-Queue-Id: 41BD6231D0 X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam02 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; + dev_access_enable(); rc = 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_device *pmem, * after clear poison. */ flush_dcache_page(page); + dev_access_enable(); write_pmem(pmem_addr, page, page_off, len); if (unlikely(bad_pmem)) { rc = pmem_clear_poison(pmem, pmem_off, len); write_pmem(pmem_addr, page, page_off, len); } + dev_access_disable(); return rc; }