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 lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 1FF66C07E9D for ; Sat, 24 Sep 2022 18:33:24 +0000 (UTC) Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4MZd1t2p3xz3dxX for ; Sun, 25 Sep 2022 04:33:22 +1000 (AEST) Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=kernel.crashing.org (client-ip=63.228.1.57; helo=gate.crashing.org; envelope-from=segher@kernel.crashing.org; receiver=) Received: from gate.crashing.org (gate.crashing.org [63.228.1.57]) by lists.ozlabs.org (Postfix) with ESMTP id 4MZd1N2jJ8z3bbP for ; Sun, 25 Sep 2022 04:32:55 +1000 (AEST) Received: from gate.crashing.org (localhost.localdomain [127.0.0.1]) by gate.crashing.org (8.14.1/8.14.1) with ESMTP id 28OIUpan005575; Sat, 24 Sep 2022 13:30:51 -0500 Received: (from segher@localhost) by gate.crashing.org (8.14.1/8.14.1/Submit) id 28OIUoYF005572; Sat, 24 Sep 2022 13:30:50 -0500 X-Authentication-Warning: gate.crashing.org: segher set sender to segher@kernel.crashing.org using -f Date: Sat, 24 Sep 2022 13:30:50 -0500 From: Segher Boessenkool To: Nicholas Piggin Subject: Re: [PATCH] powerpc/irq: Modernise inline assembly in irq_soft_mask_{set,return} Message-ID: <20220924183050.GP25951@gate.crashing.org> References: <178f30ff62c0317061f019b3dbbc079073f104c3.1663656058.git.christophe.leroy@csgroup.eu> <20220923121829.GL25951@gate.crashing.org> <20220923221543.GN25951@gate.crashing.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220923221543.GN25951@gate.crashing.org> User-Agent: Mutt/1.4.2.3i X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On Fri, Sep 23, 2022 at 05:15:43PM -0500, Segher Boessenkool wrote: > On Sat, Sep 24, 2022 at 02:26:52AM +1000, Nicholas Piggin wrote: > > I still don't see what clauses guarantees asm("%0" ::"r"(foo)) to give > > 13. It doesn't say access via inline assembly is special, > > But it is. It is for all register variables, local and global. I agree > this isn't documented clearly. For local register variables this is the > *only* thing guaranteed; for global register vars there is more (it > changes the ABI, there are safe/restore effects, that kind of thing). I filed to improve the docs. Thanks for bringing this to our attention! Segher