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=-6.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, 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 B96DEC5ACCC for ; Thu, 18 Oct 2018 18:02:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 82A4A21480 for ; Thu, 18 Oct 2018 18:02:20 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="DewpreW3" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 82A4A21480 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729748AbeJSCEY (ORCPT ); Thu, 18 Oct 2018 22:04:24 -0400 Received: from mail.kernel.org ([198.145.29.99]:52606 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729070AbeJSCEX (ORCPT ); Thu, 18 Oct 2018 22:04:23 -0400 Received: from localhost (ip-213-127-77-176.ip.prioritytelecom.net [213.127.77.176]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 5A35421476; Thu, 18 Oct 2018 18:02:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1539885737; bh=rBVOJlv3wSGRLlQK9rVSv2XUWl1FpwMRgMbadrUp0lY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=DewpreW3BX7AvVU6t3SLCieDQWjA784IIR6yXNwRBFHX1rQ0tnWE4kt8wtVpsum43 30T/kJ4u3qR1PBe4euGBlXrY6UEokCV4k/7WlodvqhyfaGfCabJBefWOri1pDlpRCU 4b8k/Q1APzuhaxlqVBbN1fsSUras3akKvXGmgEWQ= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Dave Jiang , Dan Williams , Robert Elliott , Jeff Moyer , Matthew Wilcox , Andrew Morton , Linus Torvalds , Sudip Mukherjee Subject: [PATCH 4.14 38/41] mm: disallow mappings that conflict for devm_memremap_pages() Date: Thu, 18 Oct 2018 19:54:53 +0200 Message-Id: <20181018175423.284909039@linuxfoundation.org> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20181018175416.718399607@linuxfoundation.org> References: <20181018175416.718399607@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Dave Jiang commit 15d36fecd0bdc7510b70a0e5ec6671140b3fce0c upstream. When pmem namespaces created are smaller than section size, this can cause an issue during removal and gpf was observed: general protection fault: 0000 1 SMP PTI CPU: 36 PID: 3941 Comm: ndctl Tainted: G W 4.14.28-1.el7uek.x86_64 #2 task: ffff88acda150000 task.stack: ffffc900233a4000 RIP: 0010:__put_page+0x56/0x79 Call Trace: devm_memremap_pages_release+0x155/0x23a release_nodes+0x21e/0x260 devres_release_all+0x3c/0x48 device_release_driver_internal+0x15c/0x207 device_release_driver+0x12/0x14 unbind_store+0xba/0xd8 drv_attr_store+0x27/0x31 sysfs_kf_write+0x3f/0x46 kernfs_fop_write+0x10f/0x18b __vfs_write+0x3a/0x16d vfs_write+0xb2/0x1a1 SyS_write+0x55/0xb9 do_syscall_64+0x79/0x1ae entry_SYSCALL_64_after_hwframe+0x3d/0x0 Add code to check whether we have a mapping already in the same section and prevent additional mappings from being created if that is the case. Link: http://lkml.kernel.org/r/152909478401.50143.312364396244072931.stgit@djiang5-desk3.ch.intel.com Signed-off-by: Dave Jiang Cc: Dan Williams Cc: Robert Elliott Cc: Jeff Moyer Cc: Matthew Wilcox Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sudip Mukherjee Signed-off-by: Greg Kroah-Hartman --- kernel/memremap.c | 18 +++++++++++++++++- 1 file changed, 17 insertions(+), 1 deletion(-) --- a/kernel/memremap.c +++ b/kernel/memremap.c @@ -355,10 +355,27 @@ void *devm_memremap_pages(struct device struct dev_pagemap *pgmap; struct page_map *page_map; int error, nid, is_ram, i = 0; + struct dev_pagemap *conflict_pgmap; align_start = res->start & ~(SECTION_SIZE - 1); align_size = ALIGN(res->start + resource_size(res), SECTION_SIZE) - align_start; + align_end = align_start + align_size - 1; + + conflict_pgmap = get_dev_pagemap(PHYS_PFN(align_start), NULL); + if (conflict_pgmap) { + dev_WARN(dev, "Conflicting mapping in same section\n"); + put_dev_pagemap(conflict_pgmap); + return ERR_PTR(-ENOMEM); + } + + conflict_pgmap = get_dev_pagemap(PHYS_PFN(align_end), NULL); + if (conflict_pgmap) { + dev_WARN(dev, "Conflicting mapping in same section\n"); + put_dev_pagemap(conflict_pgmap); + return ERR_PTR(-ENOMEM); + } + is_ram = region_intersects(align_start, align_size, IORESOURCE_SYSTEM_RAM, IORES_DESC_NONE); @@ -396,7 +413,6 @@ void *devm_memremap_pages(struct device mutex_lock(&pgmap_lock); error = 0; - align_end = align_start + align_size - 1; foreach_order_pgoff(res, order, pgoff) { struct dev_pagemap *dup;