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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B5633C433F5 for ; Tue, 28 Sep 2021 20:41:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9300D61373 for ; Tue, 28 Sep 2021 20:41:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242757AbhI1Un2 (ORCPT ); Tue, 28 Sep 2021 16:43:28 -0400 Received: from mail.kernel.org ([198.145.29.99]:53878 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242734AbhI1Un2 (ORCPT ); Tue, 28 Sep 2021 16:43:28 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 7887A61373 for ; Tue, 28 Sep 2021 20:41:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1632861708; bh=R6ico/w3xvjUwc0cpoYBrmW8uUbBJOufS34XYbcwsSg=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=tpNi45zs3RLsF5OUW7s1qcvIYxhsgtnJeMxEf/qOl1fOMfGLTsuQsURupwBk9UBx0 afqcOVwRV1T3OyRMYXYzUC8LaBlIGXfoKa7bsHp/EdKss73kGO1/7/9TqQOfm9h4yd DhHU6h/7ZATNKVDtT50iFrp4artTAGU6ucRvlE5XYa/A5vecQ4jJxWWIyD952VvUkB ccQHkUXHmoFrJYDk1EnZEeRv4Z1/r/TCEXpj5VYPZRJB9AF3vf09oKF1Pp5sD7gOGK v9/jza8xhPIuDTtJ9tvf3qo8ugxe2Xvp77sqijpQNXyhpKl88eZo6AfNPcWDahorm6 K9K5WXReIDU/w== Received: by mail-ot1-f49.google.com with SMTP id j11-20020a9d190b000000b00546fac94456so85058ota.6 for ; Tue, 28 Sep 2021 13:41:48 -0700 (PDT) X-Gm-Message-State: AOAM530DYyaOBqCAEZtF0jDOLmQMqhkUyivmNBdYAbJ34vVRgMmrxCms IpzMgOoIkBR9AEBMrmZI5QzTcUTWppgDPnwZLac= X-Google-Smtp-Source: ABdhPJzSSPCUEW5QAIe49opqaZ+5yBgTb1A8ZDhjodRoMqcpulQrotvkXZt6CSxazmnS9/0S7YvqaPkdBtPxKt1pAdY= X-Received: by 2002:a9d:63c7:: with SMTP id e7mr2514381otl.30.1632861707874; Tue, 28 Sep 2021 13:41:47 -0700 (PDT) MIME-Version: 1.0 References: <20210924134919.1913476-1-bigeasy@linutronix.de> <20210924134919.1913476-2-bigeasy@linutronix.de> <20210928133340.tmpjzdj367h54ddt@linutronix.de> <87k0j0a1hw.ffs@tglx> In-Reply-To: <87k0j0a1hw.ffs@tglx> From: Ard Biesheuvel Date: Tue, 28 Sep 2021 22:41:36 +0200 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH 1/2] efi: Disable runtime services on RT To: Thomas Gleixner Cc: Sebastian Andrzej Siewior , linux-efi , Ard Biesheuvel Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-efi@vger.kernel.org On Tue, 28 Sept 2021 at 22:28, Thomas Gleixner wrote: > > Ard, > > On Tue, Sep 28 2021 at 15:34, Ard Biesheuvel wrote: > > On Tue, 28 Sept 2021 at 15:33, Sebastian Andrzej Siewior > > wrote: > >> > >> On 2021-09-28 15:30:32 [+0200], Ard Biesheuvel wrote: > >> > This is generic code and the commit log only talks about arm64. How > >> > about other architectures? > >> > >> They also invoke the EFI services with disables interrupts. If they > >> provide a RTC behind spi/i2c then we end up in the same situation right? > >> Or did I misunderstand your point? > >> > > Are you sure you want to disable EFI runtime services on all x86 > > systems with PREEMPT_RT as well? > > I'm pretty sure because we've ran into inacceptable latencies with EFI > runtime services often enough. > > Since we disabled them these complaints have gone down to 0 and nobody > so far complained about their non-availability. > Excellent. > We might revisit that and make them default disabled on RT and offer a > command line option to enable them for those who really want them. > Yes this is what Sebastian's second patch provides. > Thanks, > > tglx I'll take this as an ack from you, Thomas, and queue these up for v5.16 Thanks, Ard.