From mboxrd@z Thu Jan 1 00:00:00 1970 From: Denys Vlasenko Subject: Re: [IDE] Fix build bug Date: Thu, 1 Nov 2007 18:43:16 +0000 Message-ID: <200711011843.16894.vda.linux@googlemail.com> References: <20071025135334.GA23272@linux-mips.org> <200710301134.30087.vda.linux@googlemail.com> <20071030124155.GA7582@linux-mips.org> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Return-path: Received: from nf-out-0910.google.com ([64.233.182.185]:61235 "EHLO nf-out-0910.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753571AbXKASn1 (ORCPT ); Thu, 1 Nov 2007 14:43:27 -0400 Received: by nf-out-0910.google.com with SMTP id g13so609822nfb for ; Thu, 01 Nov 2007 11:43:26 -0700 (PDT) In-Reply-To: <20071030124155.GA7582@linux-mips.org> Content-Disposition: inline Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Ralf Baechle Cc: Bartlomiej Zolnierkiewicz , Andrew Morton , linux-kernel@vger.kernel.org, linux-ide@vger.kernel.org, linux-mips@linux-mips.org, Martijn Uffing On Tuesday 30 October 2007 12:41, Ralf Baechle wrote: > On Tue, Oct 30, 2007 at 11:34:29AM +0000, Denys Vlasenko wrote: > > > On Thursday 25 October 2007 22:41, Bartlomiej Zolnierkiewicz wrote: > > > > -static const struct ide_port_info generic_chipsets[] __devinitdata = { > > > > +static struct ide_port_info generic_chipsets[] __devinitdata = { > > > > /* 0 */ DECLARE_GENERIC_PCI_DEV("Unknown", 0), > > > > > > > > { /* 1 */ > > > > > > I would prefer to not remove const from generic_chipsets[] so: > > > > > > [PATCH] drivers/ide/pci/generic: fix build for CONFIG_HOTPLUG=n > > > > > > It turns out that const and __{dev}initdata cannot be mixed currently > > > and that generic IDE PCI host driver is also affected by the same issue: > > > > > > On Thursday 25 October 2007, Ralf Baechle wrote: > > > > CC drivers/ide/pci/generic.o > > > > drivers/ide/pci/generic.c:52: error: __setup_str_ide_generic_all_on causes a > > > > +section type conflict > > > > > > [ Also reported by Martijn Uffing . ] > > > > > > This patch workarounds the problem in a bit hackish way but without > > > removing const from generic_chipsets[] (it adds const to __setup() so > > > __setup_str_ide_generic_all becomes const). > > > > You wouldn't believe how much const data is not marked as const because > > we don't have __constinitdata etc. Literally megabytes. > > The gain from marking it const is very little and once any non-const > __initdata object is added to a compilation unit all other const declarations > will have to be removed. Bad tradeoff. We can intrduce new, ro sections or teach gcc that combining const objects into non-ro sections is not a crime. I wonder why it currently disallows that. (And it does it only _somethimes_, const pointers happily go into rw sections!) -- vda