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=-1.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, 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 8F056C43331 for ; Tue, 12 Nov 2019 17:43:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5CA3B206BB for ; Tue, 12 Nov 2019 17:43:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1573580606; bh=xwxtyC0AXj0ksCo8SmNdjblvoZqcxlf8VXMMfMSNIFk=; h=References:In-Reply-To:From:Date:Subject:To:Cc:List-ID:From; b=wbx1CYsPZMQ9uLLdY8cfZ9QTA1q0cUZHYI6NlJbycxvnzHclOh43p7m4vqgYAhiWa Tnfmx0D9uevw8/2AsS5ju+Dq1DPMhilWfbJ4xg4UE2IPWiWbdkvbkb3OT2vjYZgvzh VPEsv7vXqG6g8m8qJLrhg+mbNnjPt9MBHKZ1Ndzw= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727148AbfKLRnZ (ORCPT ); Tue, 12 Nov 2019 12:43:25 -0500 Received: from mail.kernel.org ([198.145.29.99]:34024 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726960AbfKLRnZ (ORCPT ); Tue, 12 Nov 2019 12:43:25 -0500 Received: from mail-wr1-f41.google.com (mail-wr1-f41.google.com [209.85.221.41]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 60599222C2 for ; Tue, 12 Nov 2019 17:43:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1573580604; bh=xwxtyC0AXj0ksCo8SmNdjblvoZqcxlf8VXMMfMSNIFk=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=WYXd01Csut0FMBhxjI8Pr9vS9FaLHU2s7H09ewvL5b2GJdTza5MAzhWZU+0LAIS0M efVYQ0m9CP7asmxVpuEpE/lf4GjPMgDlbw+QIEYJaGPjrUqAalNhcMzXs2QuBluORg waAAczd6GGesNyaDtc6nN1NeGQPfKLn1t6Z1njAI= Received: by mail-wr1-f41.google.com with SMTP id w9so12718933wrr.0 for ; Tue, 12 Nov 2019 09:43:24 -0800 (PST) X-Gm-Message-State: APjAAAVQCGyWanyyhjIef3XjHfSenGNjeEyjIROprVcBK7Ye6Yk0nkms krgqRs9yn/7f4f5yZw0FMRm3/9Rad7e1v8zfiWkKgw== X-Google-Smtp-Source: APXvYqxF8nMeX4jg2o7yQ2IVWo8QTc9SYoxZNBeh7PxlVxrXgCbqSypO9QOFlCXMbDpiI8vIIv8ih/bmEZ2OLloYHQI= X-Received: by 2002:a5d:640b:: with SMTP id z11mr20907035wru.195.1573580602932; Tue, 12 Nov 2019 09:43:22 -0800 (PST) MIME-Version: 1.0 References: <20191111220314.519933535@linutronix.de> <20191111223052.509914905@linutronix.de> In-Reply-To: <20191111223052.509914905@linutronix.de> From: Andy Lutomirski Date: Tue, 12 Nov 2019 09:43:11 -0800 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [patch V2 10/16] x86/ioperm: Remove bitmap if all permissions dropped To: Thomas Gleixner Cc: LKML , X86 ML , Linus Torvalds , Andy Lutomirski , Stephen Hemminger , Willy Tarreau , Juergen Gross , Sean Christopherson , "H. Peter Anvin" 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 Mon, Nov 11, 2019 at 2:35 PM Thomas Gleixner wrote: > > If ioperm() results in a bitmap with all bits set (no permissions to any > I/O port), then handling that bitmap on context switch and exit to user > mode is pointless. Drop it. > > Move the bitmap exit handling to the ioport code and reuse it for both the > thread exit path and dropping it. This allows to reuse this code for the > upcoming iopl() emulation. Acked-by: Andy Lutomirski