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=-8.3 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_IN_DEF_DKIM_WL 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 A2D0AC433E1 for ; Thu, 18 Jun 2020 15:04:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7CCE120773 for ; Thu, 18 Jun 2020 15:04:34 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="QIP0WJ0p" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731282AbgFRPEa (ORCPT ); Thu, 18 Jun 2020 11:04:30 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60600 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731064AbgFRPE2 (ORCPT ); Thu, 18 Jun 2020 11:04:28 -0400 Received: from mail-lj1-x244.google.com (mail-lj1-x244.google.com [IPv6:2a00:1450:4864:20::244]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 19765C0613F0 for ; Thu, 18 Jun 2020 08:04:28 -0700 (PDT) Received: by mail-lj1-x244.google.com with SMTP id n24so7615285lji.10 for ; Thu, 18 Jun 2020 08:04:27 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=e3AaxzkJKvuJF6KN/5uB+HjzXUCfsnMRb9K1Yv0qPEs=; b=QIP0WJ0pNtpLo2KJbUw4+wbBhH7Nnk4+ZwOpPnliesoYCCasWqpMx0mMvynxG60m+Z u9PE+P5aKkxeVIOwcEMeLon6Vxu0ScvNx/Niy7Yn8ML9ty8p1K5Wm8ci57YEPFHfrR4P nuNnTB8kCWrogjZzQY7mXYIRdfoRzg01usyn60SP5OxOh7iWQEaYWfIvSZ3N8Zte4yZC Rmwzx1CddNdJNUqFG/N0Uke9o/ae2SSRn86wCciYZsKbVFC/U3vXdqP1N9vMXMDCRKEZ nivk6Tb2mzWBW2DcZpP2cyo8FA3tGarbAyFlHjAkABu/Oq6U36aYxnJ+PE3wuHAxS/BG aYWg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=e3AaxzkJKvuJF6KN/5uB+HjzXUCfsnMRb9K1Yv0qPEs=; b=Cxfu4Wg2RbXflHWbywIvH4WT2LsHuZXLvhgK5CjuoB9WxFh2Vjb1k9JpLJLxaYlcA/ DCFdXNvikKF9tIiq2L+iCtGgu+JXbTz9oJEfvj8nZU64OPFYDBOsZ7X08u/hHJ4cXkly 04wfgYjowE3inxTcbWz++rg/1cZLEcSU7f2YGdBeETkLcrdYXJFt0NDf0TQVRw/ggN7j 9A1Sg88DsfzhnU8oBSaFV5tn4xsAncWUvUxY1e0zs5/7COT7GTaX4ElYLIJ9c53jA5Sd 6/n1JaZRCvdStrxA1WTlbeAE8fh/iTIeHN8i+hWAOpxTTS+D7OoBNbU2gUIxfm7GG4Dx GoOw== X-Gm-Message-State: AOAM532YeIXc4ARHyGAHp7SXztTFlc0V2F9l8gilvpDAPiBwy1bYN8aC Cyik+GRlZWJ4C7N41wGXsHKv+xTrUy+57xMoLx01wA== X-Google-Smtp-Source: ABdhPJwvN0DsAWY3KYiObhTJs8ezFwVTnlVqyM1Aw6aFgxEL3CC4+lrTUDtkDUUgYpMKr67ZSTWxedjAX6xltpaE9DI= X-Received: by 2002:a2e:908f:: with SMTP id l15mr2330895ljg.307.1592492665864; Thu, 18 Jun 2020 08:04:25 -0700 (PDT) MIME-Version: 1.0 References: <20200616011742.138975-1-rajatja@google.com> <20200616011742.138975-4-rajatja@google.com> <20200616073249.GB30385@infradead.org> <20200617073100.GA14424@infradead.org> <20200618083646.GA1066967@kroah.com> In-Reply-To: From: Rajat Jain Date: Thu, 18 Jun 2020 08:03:49 -0700 Message-ID: Subject: Re: [PATCH 4/4] pci: export untrusted attribute in sysfs To: Andy Shevchenko Cc: Greg Kroah-Hartman , Christoph Hellwig , David Woodhouse , Lu Baolu , Joerg Roedel , Bjorn Helgaas , "Rafael J. Wysocki" , Len Brown , iommu@lists.linux-foundation.org, Linux Kernel Mailing List , linux-pci , ACPI Devel Maling List , Raj Ashok , "Krishnakumar, Lalithambika" , Mika Westerberg , Jean-Philippe Brucker , Prashant Malani , Benson Leung , Todd Broch , Alex Levin , Mattias Nissler , Rajat Jain , Bernie Keany , Aaron Durbin , Diego Rivas , Duncan Laurie , Furquan Shaikh , Jesse Barnes , Christian Kellner , Alex Williamson , "Oliver O'Halloran" Content-Type: text/plain; charset="UTF-8" Sender: linux-acpi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org Hello, On Thu, Jun 18, 2020 at 2:14 AM Andy Shevchenko wrote: > > On Thu, Jun 18, 2020 at 11:36 AM Greg Kroah-Hartman > wrote: > > > > On Thu, Jun 18, 2020 at 11:12:56AM +0300, Andy Shevchenko wrote: > > > On Wed, Jun 17, 2020 at 10:56 PM Rajat Jain wrote: > > > > On Wed, Jun 17, 2020 at 12:31 AM Christoph Hellwig wrote: > > > > > > ... > > > > > > > (and likely call it "external" instead of "untrusted". > > > > > > Which is not okay. 'External' to what? 'untrusted' has been carefully > > > chosen by the meaning of it. > > > What external does mean for M.2. WWAN card in my laptop? It's in ACPI > > > tables, but I can replace it. > > > > Then your ACPI tables should show this, there is an attribute for it, > > right? > > There is a _PLD() method, but it's for the USB devices (or optional > for others, I don't remember by heart). So, most of the ACPI tables, > alas, don't show this. > > > > This is only one example. Or if firmware of some device is altered, > > > and it's internal (whatever it means) is it trusted or not? > > > > That is what people are using policy for today, if you object to this, > > please bring it up to those developers :) > > > > So, please leave it as is (I mean name). > > > > firmware today exports this attribute, why do you not want userspace to > > also know it? To clarify, the attribute exposed by the firmware today is "ExternalFacingPort" and "external-facing" respectively: 617654aae50e ("PCI / ACPI: Identify untrusted PCI devices") 9cb30a71ac45d("PCI: OF: Support "external-facing" property") The kernel flag was named "untrusted" though, hence the assumption that "external=untrusted" is currently baked into the kernel today. IMHO, using "external" would fix that (The assumption can thus be contained in the IOMMU drivers) and at the same time allow more use of this attribute. > > > > Trust is different, yes, don't get the two mixed up please. That should > > be a different sysfs attribute for obvious reasons. > > Yes, as a bottom line that's what I meant as well. So what is the consensus here? I don't have a strong opinion - but it seemed to me Greg is saying "external" and Andy is saying "untrusted"? Thanks, Rajat > > -- > With Best Regards, > Andy Shevchenko