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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 52E76C54E8D for ; Mon, 11 May 2020 10:39:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 31FE8206F5 for ; Mon, 11 May 2020 10:39:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729541AbgEKKjo (ORCPT ); Mon, 11 May 2020 06:39:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59930 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1728209AbgEKKjn (ORCPT ); Mon, 11 May 2020 06:39:43 -0400 Received: from Galois.linutronix.de (Galois.linutronix.de [IPv6:2a0a:51c0:0:12e:550::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 775CEC061A0C for ; Mon, 11 May 2020 03:39:43 -0700 (PDT) Received: from p5de0bf0b.dip0.t-ipconnect.de ([93.224.191.11] helo=nanos.tec.linutronix.de) by Galois.linutronix.de with esmtpsa (TLS1.2:DHE_RSA_AES_256_CBC_SHA256:256) (Exim 4.80) (envelope-from ) id 1jY5q2-0002z3-Ev; Mon, 11 May 2020 12:39:11 +0200 Received: by nanos.tec.linutronix.de (Postfix, from userid 1000) id 76327FFBF8; Mon, 11 May 2020 12:39:09 +0200 (CEST) From: Thomas Gleixner To: Andy Lutomirski Cc: LKML , X86 ML , "Paul E. McKenney" , Andy Lutomirski , Alexandre Chartre , Frederic Weisbecker , Paolo Bonzini , Sean Christopherson , Masami Hiramatsu , Petr Mladek , Steven Rostedt , Joel Fernandes , Boris Ostrovsky , Juergen Gross , Brian Gerst , Mathieu Desnoyers , Josh Poimboeuf , Will Deacon Subject: Re: [patch V4 part 3 10/29] x86/idtentry: Provide macros to define/declare IDT entry points In-Reply-To: References: <20200505134354.774943181@linutronix.de> <20200505134904.273363275@linutronix.de> Date: Mon, 11 May 2020 12:39:09 +0200 Message-ID: <87blmu4uya.fsf@nanos.tec.linutronix.de> MIME-Version: 1.0 Content-Type: text/plain X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1,SHORTCIRCUIT=-0.0001 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Andy Lutomirski writes: > On Tue, May 5, 2020 at 7:15 AM Thomas Gleixner wrote: >> >> Provide DECLARE/DEFINE_IDTENTRY() macros. > > Acked-by: Andy Lutomirski > > except: > >> >> DEFINE_IDTENTRY() provides a wrapper which acts as the function >> definition. The exception handler body is just appended to it with curly >> brackets. The entry point is marked notrace/noprobe so that irq tracing and >> the enter_from_user_mode() can be moved into the C-entry point. > > "noinstr", perhaps? I'm guessing you write this text before noinstr > happened. Yes. > Also, would it perhaps make sense in the future to include the > idtentry macro somehow (via inline asm or gcc options) so that > DEFINE_IDTENTRY() could emit the stub instead of leaving it to > DECLARE_IDTENTRY()? It might end up too messy in practice, I suppose. > This is obviously not worth changing right now, but maybe down the > road. Maybe. Right now my entry/rcu/tracing induced brainmelt is far too advanced to try thinking about it :)