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=-3.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, UNPARSEABLE_RELAY,URIBL_BLOCKED autolearn=no 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 3A435C433C1 for ; Fri, 26 Mar 2021 21:14:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 154A661A2A for ; Fri, 26 Mar 2021 21:14:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230318AbhCZVOL (ORCPT ); Fri, 26 Mar 2021 17:14:11 -0400 Received: from sibelius.xs4all.nl ([83.163.83.176]:53517 "EHLO sibelius.xs4all.nl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229957AbhCZVNh (ORCPT ); Fri, 26 Mar 2021 17:13:37 -0400 Received: from localhost (bloch.sibelius.xs4all.nl [local]) by bloch.sibelius.xs4all.nl (OpenSMTPD) with ESMTPA id 753b7a91; Fri, 26 Mar 2021 22:13:35 +0100 (CET) Date: Fri, 26 Mar 2021 22:13:35 +0100 (CET) From: Mark Kettenis To: Arnd Bergmann Cc: sven@svenpeter.dev, robh@kernel.org, iommu@lists.linux-foundation.org, joro@8bytes.org, will@kernel.org, robin.murphy@arm.com, marcan@marcan.st, maz@kernel.org, mohamed.mediouni@caramail.com, stan@corellium.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org In-Reply-To: (message from Arnd Bergmann on Fri, 26 Mar 2021 21:03:32 +0100) Subject: Re: [PATCH 0/3] Apple M1 DART IOMMU driver References: <20210320151903.60759-1-sven@svenpeter.dev> <20210323205346.GA1283560@robh.at.kernel.org> <43685c67-6d9c-4e72-b320-0462c2273bf0@www.fastmail.com> <9f06872d-f0ec-43c3-9b53-d144337100b3@www.fastmail.com> Message-ID: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > From: Arnd Bergmann > Date: Fri, 26 Mar 2021 21:03:32 +0100 > > On Fri, Mar 26, 2021 at 6:28 PM Mark Kettenis wrote: > > > I haven't figured out how the bypass stuff really works. Corellium > > added support for it in their codebase when they added support for > > Thunderbolt, and some of the DARTs that seem to be related to > > Thunderbolt do indeed have a "bypass" property. But it is unclear to > > me how the different puzzle pieces fit together for Thunderbolt. > > As a general observation, bypass mode for Thunderbolt is what enabled > the http://thunderclap.io/ attack. This is extremely useful for debugging > a running kernel from another machine, but it's also something that > should never be done in a production kernel. No kidding! I was surprised to see the bypass support on the Thunderbolt-related nodes. 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=-3.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, UNPARSEABLE_RELAY,URIBL_BLOCKED autolearn=no 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 C8E15C433C1 for ; Fri, 26 Mar 2021 21:13:45 +0000 (UTC) Received: from smtp4.osuosl.org (smtp4.osuosl.org [140.211.166.137]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 420D5619CB for ; Fri, 26 Mar 2021 21:13:45 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 420D5619CB Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=xs4all.nl Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=iommu-bounces@lists.linux-foundation.org Received: from localhost (localhost [127.0.0.1]) by smtp4.osuosl.org (Postfix) with ESMTP id E598141869; Fri, 26 Mar 2021 21:13:44 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp4.osuosl.org ([127.0.0.1]) by localhost (smtp4.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id POGlmBRs-KAi; Fri, 26 Mar 2021 21:13:44 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [IPv6:2605:bc80:3010:104::8cd3:938]) by smtp4.osuosl.org (Postfix) with ESMTP id 9E6634185C; Fri, 26 Mar 2021 21:13:43 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id 68C72C000C; Fri, 26 Mar 2021 21:13:43 +0000 (UTC) Received: from smtp2.osuosl.org (smtp2.osuosl.org [140.211.166.133]) by lists.linuxfoundation.org (Postfix) with ESMTP id 8679DC000A for ; Fri, 26 Mar 2021 21:13:42 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp2.osuosl.org (Postfix) with ESMTP id 665A34060F for ; Fri, 26 Mar 2021 21:13:42 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp2.osuosl.org ([127.0.0.1]) by localhost (smtp2.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id wPDTbGjFVjG7 for ; Fri, 26 Mar 2021 21:13:40 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.8.0 Received: from sibelius.xs4all.nl (sibelius.xs4all.nl [83.163.83.176]) by smtp2.osuosl.org (Postfix) with ESMTPS id EE01040245 for ; Fri, 26 Mar 2021 21:13:39 +0000 (UTC) Received: from localhost (bloch.sibelius.xs4all.nl [local]) by bloch.sibelius.xs4all.nl (OpenSMTPD) with ESMTPA id 753b7a91; Fri, 26 Mar 2021 22:13:35 +0100 (CET) Date: Fri, 26 Mar 2021 22:13:35 +0100 (CET) From: Mark Kettenis To: Arnd Bergmann In-Reply-To: (message from Arnd Bergmann on Fri, 26 Mar 2021 21:03:32 +0100) Subject: Re: [PATCH 0/3] Apple M1 DART IOMMU driver References: <20210320151903.60759-1-sven@svenpeter.dev> <20210323205346.GA1283560@robh.at.kernel.org> <43685c67-6d9c-4e72-b320-0462c2273bf0@www.fastmail.com> <9f06872d-f0ec-43c3-9b53-d144337100b3@www.fastmail.com> Message-ID: Cc: robh@kernel.org, sven@svenpeter.dev, devicetree@vger.kernel.org, will@kernel.org, marcan@marcan.st, linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org, maz@kernel.org, mohamed.mediouni@caramail.com, robin.murphy@arm.com, linux-arm-kernel@lists.infradead.org, stan@corellium.com X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Development issues for Linux IOMMU support List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: iommu-bounces@lists.linux-foundation.org Sender: "iommu" > From: Arnd Bergmann > Date: Fri, 26 Mar 2021 21:03:32 +0100 > > On Fri, Mar 26, 2021 at 6:28 PM Mark Kettenis wrote: > > > I haven't figured out how the bypass stuff really works. Corellium > > added support for it in their codebase when they added support for > > Thunderbolt, and some of the DARTs that seem to be related to > > Thunderbolt do indeed have a "bypass" property. But it is unclear to > > me how the different puzzle pieces fit together for Thunderbolt. > > As a general observation, bypass mode for Thunderbolt is what enabled > the http://thunderclap.io/ attack. This is extremely useful for debugging > a running kernel from another machine, but it's also something that > should never be done in a production kernel. No kidding! I was surprised to see the bypass support on the Thunderbolt-related nodes. _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu 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=-4.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY,URIBL_BLOCKED autolearn=no 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 3167DC433C1 for ; Fri, 26 Mar 2021 21:16:25 +0000 (UTC) Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id D2062619F7 for ; Fri, 26 Mar 2021 21:16:24 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D2062619F7 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=xs4all.nl Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=desiato.20200630; h=Sender:Content-Transfer-Encoding :Content-Type:MIME-Version:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:Message-ID:References:Subject:In-Reply-To:Cc:To:From :Date:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=QLRyE4T+Qggr+KQT+3I+T8uNNg9IYbztv2nb2br8Ux4=; b=Dkb7FmzejDj40730TfuP+qR3bf TttUoet0hCmHWNOuJ5jodhlCq69D+RKVnkUYdm5oDekKLIVgIg5e1hNqV8DPPmHiVtZRh1DxFfupt 0JlweZQS3/snTMOLXbjD51BZwYH3h0NJFncMb+Ij7gyYDvBiv8sRv8w2gWlxqVN7if7pVG2kJ5oQM Ezoo1Ka79YzHTeJPQA+aNdX9E285d4UApll25X6mTPTBL/DNMU655hn7BKG18x6pkw7p60+S8Z2wc cM/AugH5p3QKAhCqWi5rV426DB2/tcAlmkcv1LDEe+hPrD857HWTwLt9Yx1DOc2+tOgu+5VgMEMDs kKspZsZw==; Received: from localhost ([::1] helo=desiato.infradead.org) by desiato.infradead.org with esmtp (Exim 4.94 #2 (Red Hat Linux)) id 1lPtm9-004MKS-Vl; Fri, 26 Mar 2021 21:13:50 +0000 Received: from sibelius.xs4all.nl ([83.163.83.176]) by desiato.infradead.org with esmtps (Exim 4.94 #2 (Red Hat Linux)) id 1lPtlx-004MJ5-2P for linux-arm-kernel@lists.infradead.org; Fri, 26 Mar 2021 21:13:39 +0000 Received: from localhost (bloch.sibelius.xs4all.nl [local]) by bloch.sibelius.xs4all.nl (OpenSMTPD) with ESMTPA id 753b7a91; Fri, 26 Mar 2021 22:13:35 +0100 (CET) Date: Fri, 26 Mar 2021 22:13:35 +0100 (CET) From: Mark Kettenis To: Arnd Bergmann Cc: sven@svenpeter.dev, robh@kernel.org, iommu@lists.linux-foundation.org, joro@8bytes.org, will@kernel.org, robin.murphy@arm.com, marcan@marcan.st, maz@kernel.org, mohamed.mediouni@caramail.com, stan@corellium.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org In-Reply-To: (message from Arnd Bergmann on Fri, 26 Mar 2021 21:03:32 +0100) Subject: Re: [PATCH 0/3] Apple M1 DART IOMMU driver References: <20210320151903.60759-1-sven@svenpeter.dev> <20210323205346.GA1283560@robh.at.kernel.org> <43685c67-6d9c-4e72-b320-0462c2273bf0@www.fastmail.com> <9f06872d-f0ec-43c3-9b53-d144337100b3@www.fastmail.com> Message-ID: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210326_211337_414346_DCFA03C9 X-CRM114-Status: GOOD ( 12.13 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org > From: Arnd Bergmann > Date: Fri, 26 Mar 2021 21:03:32 +0100 > > On Fri, Mar 26, 2021 at 6:28 PM Mark Kettenis wrote: > > > I haven't figured out how the bypass stuff really works. Corellium > > added support for it in their codebase when they added support for > > Thunderbolt, and some of the DARTs that seem to be related to > > Thunderbolt do indeed have a "bypass" property. But it is unclear to > > me how the different puzzle pieces fit together for Thunderbolt. > > As a general observation, bypass mode for Thunderbolt is what enabled > the http://thunderclap.io/ attack. This is extremely useful for debugging > a running kernel from another machine, but it's also something that > should never be done in a production kernel. No kidding! I was surprised to see the bypass support on the Thunderbolt-related nodes. _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel