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=-8.4 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,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 94058C43141 for ; Tue, 3 Dec 2019 19:41:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 67C0720803 for ; Tue, 3 Dec 2019 19:41:46 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="Zn6/mtS4" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727219AbfLCTlp (ORCPT ); Tue, 3 Dec 2019 14:41:45 -0500 Received: from mail-io1-f46.google.com ([209.85.166.46]:39431 "EHLO mail-io1-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726659AbfLCTlp (ORCPT ); Tue, 3 Dec 2019 14:41:45 -0500 Received: by mail-io1-f46.google.com with SMTP id c16so5130776ioh.6 for ; Tue, 03 Dec 2019 11:41:44 -0800 (PST) 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=FBemf5DffbM9H45GJNpf6XQTgytqS7SHwtWxDozwP2k=; b=Zn6/mtS46CfYNTBvL+G3gsuGdj1yDZoKrME2Cm0wMQCY5fjcoWvefbN1CLMGjmOJA1 9WC2PCtFU8/4Vfd86+YWCUQIvD9IOjXz34uyx/oizThOidMc1Rr0u0foU+ENh1eWzRRd 6l8ow8Ls2e3YVJifDJ0mtA6n/3ev0jFO8JJ+Tetw55fE3BZW/65tDfu58DYHWpL900Hb z5JrdoFih7F7WjFZ6OB4c0Tm/Qbd8PQ3GaRoIQa9kfq1Db5dV1NprGktZwf6GGHsNcmE YGHLmKd1Je58e3wvoMtiPxTd4xKzZD57TXT4CL0ZVrlbTrU3JZaYltoYxGOJIFmjwp54 a48g== 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=FBemf5DffbM9H45GJNpf6XQTgytqS7SHwtWxDozwP2k=; b=Gwdqz1TlpRUQ5Qd47+g0Fn9cAyTnEdjsOcdW2yW1e914PpzURohKVznA90aRVFG3AD Tx4ta4RmeFsUHaquyh746Rrh7dg0ycuTDXVYt6OCiT03Fz2UgRnBtkH+uAMSL6iKvz1s BGlXJ3jB6L/D8QF/BmrMSTq4xZmRdzaHs4Ebz6XJmJtdZpZ0gcQvWxXyRVeiuPTHb5qm Dg7wNBlUwyntS0VpXIYTstAP8QIgkAatQ+xAs3IUvKM3mhN9hsjbkASBxJRI6MC+0MwG wSHJyJYCzQUynFN0TQ0AB3oUeJlyTe97h5DdB54WEqp6zecLPNFpG3uEtCcSw2IpmS1t OP9A== X-Gm-Message-State: APjAAAVSHHh6iOrVEAia4uFRBNMY9nByMVi0hfi0ZZgrsKkRIabo7WT8 QzYE1dgzdfH3yh9yKWkw520iGAiLQH12JR9fBFXnsQ== X-Google-Smtp-Source: APXvYqwxkVJgS3InUv5/LmPbRiof3P9j+j9W7/spqafHaIbJnIhprxg1ULJPZZFP78UueZBNHl/exmw8VSDIniSdL/k= X-Received: by 2002:a5d:9913:: with SMTP id x19mr3905793iol.46.1575402104183; Tue, 03 Dec 2019 11:41:44 -0800 (PST) MIME-Version: 1.0 References: <20191203004043.174977-1-matthewgarrett@google.com> In-Reply-To: From: Matthew Garrett Date: Tue, 3 Dec 2019 11:41:32 -0800 Message-ID: Subject: Re: [PATCH] [EFI,PCI] Allow disabling PCI busmastering on bridges during boot To: Andy Lutomirski Cc: linux-efi , Ard Biesheuvel , X86 ML , linux-pci , LKML Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Dec 3, 2019 at 7:30 AM Andy Lutomirski wrote: > Would a similar patch apply to non-EFI boot? That is, in a BIOS boot, > is busmastering on when the kernel is loaded? It's only relevant where firmware configures the IOMMU but then removes that configuration before handing control to the OS. I'm not aware of that happening anywhere other than EFI.