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=-2.0 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 306BBC2D0C0 for ; Mon, 23 Dec 2019 16:12:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 03A5D20709 for ; Mon, 23 Dec 2019 16:12:28 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="fTifpCmR" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726749AbfLWQM1 (ORCPT ); Mon, 23 Dec 2019 11:12:27 -0500 Received: from mail-qv1-f65.google.com ([209.85.219.65]:45773 "EHLO mail-qv1-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726744AbfLWQM1 (ORCPT ); Mon, 23 Dec 2019 11:12:27 -0500 Received: by mail-qv1-f65.google.com with SMTP id l14so6504393qvu.12 for ; Mon, 23 Dec 2019 08:12:27 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:from:date:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=tk71JQngaMAIzNPkkgd8t13g13HLGutomGGTzi0KCmU=; b=fTifpCmR/0kiTE0DX0JcrhlxcjX7GkJaT5UOwXNYvut0G+6HBUhMlmVEKZiLbAVB/F DvOfvVH6uQ+lgN2MhHHRHqMgwTxFAHIEafB6dFw0aXIU2a2DOQMgfAKwMGCkRX07GxDJ TS4m/h5xOFM1i5kmORJ4Gn1NrBbT3m7QFMrUN9Smfte84mU/6ly85mfYcBuvClCjkKPv zdxEa/96OX9vn/wDikhSKOg01rGxlCPo1SK+5lrbTv3HKG/MOtEhzvaIjkG3N1HOLTZ+ LRi3ZW40xDbGOuB/IFjEwTLYpMpy09oSr2MrEEHmRmm8VdKLkOb4LN88u9cWYoRdlP/t Cjsg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:from:date:to:cc:subject:message-id :references:mime-version:content-disposition:in-reply-to:user-agent; bh=tk71JQngaMAIzNPkkgd8t13g13HLGutomGGTzi0KCmU=; b=qsBh9AmXwHGrRmKidmiRipYaye7cxJNQvasSAl9AUntTgABHI7QR698zavUaLqC0Fx zMAfEKwiRi5aggxpjn3KdTNdkgxooWh+eW4lRF16dl5oUPBn2SD8ADB+ukXF9ZHrZ2g4 Ca5uAu6GJ+i+0uN/T4aVNdcs00DAwNOQSDNr4RsE9GG17HbUTatl7f0cPy75cQs8OFDT dj/QxRDPHglv23RETUnewiS5vwYg3Gr8yzD6b2W30uAm5LyWcYLnhbrDqL+SujB1Hvyy aNclFXiTcVvGAc2lWeDGmrDbCJmxVyvhRQbeOq9lGvqdztaohJNq2b486KEILUrAny18 QXrg== X-Gm-Message-State: APjAAAXgcW4qQgYokBiVVEw/cRJerW0W7TZALxpWgUeMGwHYqWu9GQqo onjxdyo/0PkKOaZlb1nEMPM= X-Google-Smtp-Source: APXvYqzoRSp64k3I7G4OoMaGh6YgsieIyKC9J7Dp/4atnlJk4Hm2q+ycKFNTktrM0i57jqOeOKr5kQ== X-Received: by 2002:a05:6214:bc6:: with SMTP id ff6mr24116765qvb.133.1577117546254; Mon, 23 Dec 2019 08:12:26 -0800 (PST) Received: from rani.riverdale.lan ([2001:470:1f07:5f3::b55f]) by smtp.gmail.com with ESMTPSA id 2sm5901419qkv.98.2019.12.23.08.12.25 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 23 Dec 2019 08:12:26 -0800 (PST) From: Arvind Sankar X-Google-Original-From: Arvind Sankar Date: Mon, 23 Dec 2019 11:12:24 -0500 To: Ard Biesheuvel Cc: Arvind Sankar , Matthew Garrett , Ard Biesheuvel , linux-efi , Hans de Goede , Ingo Molnar , Andy Lutomirski , Thomas Gleixner Subject: Re: [PATCH v2 21/21] efi: Allow disabling PCI busmastering on bridges during boot Message-ID: <20191223161224.GA18630@rani.riverdale.lan> References: <20191218170139.9468-22-ardb@kernel.org> <20191221225426.GA6970@rani.riverdale.lan> <20191223154648.GA10522@rani.riverdale.lan> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-efi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-efi@vger.kernel.org On Mon, Dec 23, 2019 at 04:58:26PM +0100, Ard Biesheuvel wrote: > On Mon, 23 Dec 2019 at 16:46, Arvind Sankar wrote: > > > > On Mon, Dec 23, 2019 at 03:02:40PM +0100, Ard Biesheuvel wrote: > > > > > > Practically, on PCIe systems, PCI/PCI bridges are the only thing we > > > need to care about, since that is how PCIe root ports are modelled. > > > > If I'm interpreting my lspci output correctly, I have a PCI/ISA bridge > > on bus 0 that's not behind a PCI/PCI bridge. Device 1f.0 below is the > > PCI/ISA bridge. > > Yeah, this is the LPC controller, right? What devices are actually on > that bus that are not closely tied to the chipset? > AFAICT it's my BMC's IPMI interface and some sort of watchdog I think -- don't have drivers but there are three other ACPI PNP* nodes under there as well.