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=-11.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 99467C4320A for ; Tue, 31 Aug 2021 20:22:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 82FCC6103A for ; Tue, 31 Aug 2021 20:22:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241229AbhHaUXK (ORCPT ); Tue, 31 Aug 2021 16:23:10 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:43849 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241170AbhHaUWy (ORCPT ); Tue, 31 Aug 2021 16:22:54 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1630441318; 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=uZxqGuQje81ADCZ63+jKstcc7DkOvzy6fvXKAVNR7aM=; b=i/84Dn61jW5900zD13LlNt4bc3dINwwWVXv626mErfR2SDuFJGtEBnyfFzompw8EDJGkpz dp41NMiDC+q+lVS7Gs/I16Ard1YCtZa7tlmwwkNbAgu9P8dZSghHyPbh4Vasz39pl7y0Zj ycIarjQbDWJBf7vTbsgH6wt0CXffrd0= 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-53-38Rga71YN_SbSIAwL7BGvw-1; Tue, 31 Aug 2021 16:21:54 -0400 X-MC-Unique: 38Rga71YN_SbSIAwL7BGvw-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id D7527EC1A0; Tue, 31 Aug 2021 20:21:52 +0000 (UTC) Received: from t480s.redhat.com (unknown [10.39.194.183]) by smtp.corp.redhat.com (Postfix) with ESMTP id 4CE9318649; Tue, 31 Aug 2021 20:21:42 +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 v3 0/3] virtio-mem: disallow mapping virtio-mem memory via /dev/mem Date: Tue, 31 Aug 2021 22:21:38 +0200 Message-Id: <20210831202141.13846-1-david@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org I think this might be a good fit for the -mm tree, as the actual virtio-mem changes are rather small. -- Let's add the basic infrastructure to exclude some physical memory regions marked as "IORESOURCE_SYSTEM_RAM" completely from /dev/mem access, even though they are not marked IORESOURCE_BUSY and even though "iomem=relaxed" is set. Resource IORESOURCE_EXCLUSIVE for that purpose instead of adding new flags to express something similar to "soft-busy" or "not busy yet, but already prepared by a driver and not to be mapped by user space". 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. Details can be found in patch #2 and #3. v2 -> v3: - "kernel/resource: clean up and optimize iomem_is_exclusive()" -- Reshuffled and moved for_each_resource() etc. into this patch - "kernel/resource: disallow access to exclusive system RAM regions" -- Leave CONFIG_STRICT_DEVMEM=n alone. Hoog into iomem_is_exclusive() instead. -- Improve comments - "virtio-mem: disallow mapping virtio-mem memory via /dev/mem" -- Don't allow building virtio_mem without CONFIG_STRICT_DEVMEM when we have CONFIG_DEVMEM, where we don't have any guarantees. - Rework all patch descriptions 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): kernel/resource: clean up and optimize iomem_is_exclusive() kernel/resource: disallow access to exclusive system RAM regions virtio-mem: disallow mapping virtio-mem memory via /dev/mem drivers/virtio/Kconfig | 1 + drivers/virtio/virtio_mem.c | 4 ++- kernel/resource.c | 54 ++++++++++++++++++++++++++----------- 3 files changed, 43 insertions(+), 16 deletions(-) base-commit: 7d2a07b769330c34b4deabeed939325c77a7ec2f -- 2.31.1