From patchwork Mon Aug 16 14:25:02 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Hildenbrand X-Patchwork-Id: 12438727 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=-8.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 608FEC4338F for ; Mon, 16 Aug 2021 14:25:25 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 011AA6108E for ; Mon, 16 Aug 2021 14:25:24 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 011AA6108E Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvack.org Received: by kanga.kvack.org (Postfix) id 748276B0073; Mon, 16 Aug 2021 10:25:24 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 6F6F56B0074; Mon, 16 Aug 2021 10:25:24 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 5E6718D0001; Mon, 16 Aug 2021 10:25:24 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0140.hostedemail.com [216.40.44.140]) by kanga.kvack.org (Postfix) with ESMTP id 436196B0073 for ; Mon, 16 Aug 2021 10:25:24 -0400 (EDT) Received: from smtpin18.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id CD16218244EE9 for ; Mon, 16 Aug 2021 14:25:23 +0000 (UTC) X-FDA: 78481166526.18.52A9BEF Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [216.205.24.124]) by imf27.hostedemail.com (Postfix) with ESMTP id 7AE8A700E5D1 for ; Mon, 16 Aug 2021 14:25:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1629123922; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=+xHuOgld2yV1Ehb4bmgL8GwSOGfxwi16qCP0g5oXrXY=; b=GT2VXOV+4gmwdbnFdjxsldEaHiOzLG0DZ5bJSthiWLia1zBf5OYwAPHudSxfv/VV0wIK+V 3YLykpDaOBrz9mQB0MfTgRGu0sSlR12KeuIAXp/KFLgoxm2Jkx6UeXdPBXSKhAjp5SplJR 2QsB1Pjh+dnMW83yKeKv5WYrgx+XFhs= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-119-2F8IBltuPrGtTbM92SS1vw-1; Mon, 16 Aug 2021 10:25:21 -0400 X-MC-Unique: 2F8IBltuPrGtTbM92SS1vw-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id B0E19190A7AD; Mon, 16 Aug 2021 14:25:19 +0000 (UTC) Received: from t480s.redhat.com (unknown [10.39.192.85]) by smtp.corp.redhat.com (Postfix) with ESMTP id 2BB83E728; Mon, 16 Aug 2021 14:25:05 +0000 (UTC) From: David Hildenbrand To: linux-kernel@vger.kernel.org Cc: David Hildenbrand , Arnd Bergmann , Greg Kroah-Hartman , "Michael S. Tsirkin" , Jason Wang , "Rafael J. Wysocki" , Andrew Morton , Dan Williams , Hanjun Guo , Andy Shevchenko , virtualization@lists.linux-foundation.org, linux-mm@kvack.org Subject: [PATCH v2 0/3] virtio-mem: disallow mapping virtio-mem memory via /dev/mem Date: Mon, 16 Aug 2021 16:25:02 +0200 Message-Id: <20210816142505.28359-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: 7AE8A700E5D1 X-Stat-Signature: q8humxefakyjbnj48eo1a9adfqgduumq Authentication-Results: imf27.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b=GT2VXOV+; dmarc=pass (policy=none) header.from=redhat.com; spf=none (imf27.hostedemail.com: domain of david@redhat.com has no SPF policy when checking 216.205.24.124) smtp.mailfrom=david@redhat.com X-HE-Tag: 1629123923-311180 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: Let's add the basic infrastructure to exclude some physical memory regions completely from /dev/mem access, on any architecture and under any system configuration (independent of CONFIG_STRICT_DEVMEM and independent of "iomem="). Use it for virtio-mem, to disallow mapping any virtio-mem memory via /dev/mem to user space after the virtio-mem driver was loaded: there is no sane use case to access the device-managed memory region via /dev/mem once the driver is actively (un)plugging memory within that region and we want to make sure that nobody will accidentially access unplugged memory in a sane environment. Details can be found in patch #1. v1 -> v2: - "/dev/mem: disallow access to explicitly excluded system RAM regions" -- Introduce and use for_each_resource() and next_resource_skip_children() -- s/iomem_range_contains_excluded/iomem_range_contains_excluded_devmem/ - "kernel/resource: cleanup and optimize iomem_is_exclusive()" -- Use for_each_resource() Cc: Arnd Bergmann Cc: Greg Kroah-Hartman Cc: "Michael S. Tsirkin" Cc: Jason Wang Cc: "Rafael J. Wysocki" Cc: Andrew Morton Cc: Dan Williams Cc: Hanjun Guo Cc: Andy Shevchenko Cc: virtualization@lists.linux-foundation.org Cc: linux-mm@kvack.org David Hildenbrand (3): /dev/mem: disallow access to explicitly excluded system RAM regions virtio-mem: disallow mapping virtio-mem memory via /dev/mem kernel/resource: cleanup and optimize iomem_is_exclusive() drivers/char/mem.c | 22 ++++++-------- drivers/virtio/virtio_mem.c | 4 ++- include/linux/ioport.h | 1 + kernel/resource.c | 60 +++++++++++++++++++++++++++++++++---- lib/Kconfig.debug | 4 ++- 5 files changed, 71 insertions(+), 20 deletions(-) base-commit: 7c60610d476766e128cc4284bb6349732cbd6606