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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 68B0EC433F5 for ; Mon, 30 May 2022 16:56:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242184AbiE3Q4S (ORCPT ); Mon, 30 May 2022 12:56:18 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43174 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241161AbiE3Q4P (ORCPT ); Mon, 30 May 2022 12:56:15 -0400 Received: from pandora.armlinux.org.uk (pandora.armlinux.org.uk [IPv6:2001:4d48:ad52:32c8:5054:ff:fe00:142]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 04E0FA777C for ; Mon, 30 May 2022 09:56:14 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=armlinux.org.uk; s=pandora-2019; h=Sender:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=UykJ1IPICNFbfEo420X6Xx726q411APwSMuLoQTgdDo=; b=dMiLt0/Fv3cJXwMowD9p3ULFzI yzsGHXFL2yUq6S8ZTXuMQ0q5JZbcQCSd0umLh+lXFdY+97OggxB2MlCPgF2OGicJDAlFkuKajONDY 7UabLE+JTBG7aSarulxeIHWW2YauCNc6f6OoUmSXPZ9O92BuzFPDy0TIlHKNeF4B8TXuTHhWhaIOa C5Q6WtENs7aXBgbZ9GsEGMB8VcQFpRC2QTuoOiHATWKJ4YFeJYTdEJ8hFpCzcnhj1NgETylwtSF22 BO7HJuet5IcF7H3lHpcNaikDEhnof+/f0rcBweFI5o3ekb7Mhp24t9sAjod4cTd84zXRRX/Efe0GZ rYesoOEA==; Received: from shell.armlinux.org.uk ([fd8f:7570:feb6:1:5054:ff:fe00:4ec]:60890) by pandora.armlinux.org.uk with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1nvigZ-00046W-AO; Mon, 30 May 2022 17:56:07 +0100 Received: from linux by shell.armlinux.org.uk with local (Exim 4.94.2) (envelope-from ) id 1nvigY-0001Ze-Lg; Mon, 30 May 2022 17:56:06 +0100 Date: Mon, 30 May 2022 17:56:06 +0100 From: "Russell King (Oracle)" To: Arnd Bergmann Cc: Jani Nikula , Linus Torvalds , Sudip Mukherjee , Viresh Kumar , Shiraz Hashim , Ville =?iso-8859-1?Q?Syrj=E4l=E4?= , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Daniel Vetter , dri-devel , Linux Kernel Mailing List , Linux ARM , SoC Team Subject: Re: mainline build failure due to f1e4c916f97f ("drm/edid: add EDID block count and size helpers") Message-ID: References: <87a6aztli2.fsf@intel.com> <877d63tleq.fsf@intel.com> <87czfvrwsv.fsf@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: Russell King (Oracle) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, May 30, 2022 at 03:35:28PM +0200, Arnd Bergmann wrote: > The annotations for edid are completely correct and necessary. However > other driver authors just slap __packed annotations on any structure > even if the layout is not fixed at all like: > > struct my_driver_priv { > struct device dev; > u8 causes_misalignment; > spinlock_t lock; > atomic_t counter; > } __packed; /* this annotation is harmful because it breaks the atomics */ > > or if the annotation does not change the layout like > > struct my_dma_descriptor { > __le64 address; > __le64 length; > } __packed; /* does not change layout but makes access slow on some > architectures */ Sounds like we need a howto document for people to ignore and continue doing their own thing. :P -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTP is here! 40Mbps down 10Mbps up. Decent connectivity at last!