Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932422AbXAVUbv (ORCPT ); Mon, 22 Jan 2007 15:31:51 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932186AbXAVUbv (ORCPT ); Mon, 22 Jan 2007 15:31:51 -0500 Received: from an-out-0708.google.com ([209.85.132.240]:28602 "EHLO an-out-0708.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932422AbXAVUbu (ORCPT ); Mon, 22 Jan 2007 15:31:50 -0500 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=beta; h=received:message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=O2caD9Hz9UvIcALEticftZZrFEsDunqgjAOK/9u9uBIzIVm6F9jZrHxSeLvmb4EMRnUqrxWzFECH07ZjIMy9Ks3/OCBG4REfrAiPOL3ox2ucSE3gy6lwHYCy7xsN+vNRFccg1HiBYCnfweFha39qusW8D6HkGphlDU7r3euhjUc= Message-ID: <9e0cf0bf0701221231sc638114j2f0123650ffc14ea@mail.gmail.com> Date: Mon, 22 Jan 2007 22:31:48 +0200 From: "Alon Bar-Lev" To: "Andrew Morton" Subject: Re: [patch 03/26] Dynamic kernel command-line - arm Cc: "Russell King" , tom@dbservice.com, bwalle@suse.de, linux-kernel@vger.kernel.org In-Reply-To: <20070122115650.d0be8bd3.akpm@osdl.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <20070118125849.441998000@strauss.suse.de> <20070118130028.719472000@strauss.suse.de> <20070118141359.GB31418@flint.arm.linux.org.uk> <45AF92E7.50901@dbservice.com> <20070118152326.GC31418@flint.arm.linux.org.uk> <20070122115650.d0be8bd3.akpm@osdl.org> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2163 Lines: 54 Hello Andrew, Can I do anything more in order to be closer to merge? Some general comments... or should I CC other people etc... I submitted this several times but got almost no architecture to ACK. I just don't know how we can progress with this issue... All we wanted is to break the 256 limit in x86... Best Regards, Alon Bar-Lev. On 1/22/07, Andrew Morton wrote: > > On Thu, 18 Jan 2007 15:23:26 +0000 Russell King wrote: > > On Thu, Jan 18, 2007 at 04:31:51PM +0100, Tomas Carnecky wrote: > > > Russell King wrote: > > > > On Thu, Jan 18, 2007 at 01:58:52PM +0100, Bernhard Walle wrote: > > > >> -static char command_line[COMMAND_LINE_SIZE]; > > > >> +static char __initdata command_line[COMMAND_LINE_SIZE]; > > > > > > > > Uninitialised data is placed in the BSS. Adding __initdata to BSS > > > > data causes grief. > > > > > > > > > > Static variables are implicitly initialized to zero. Does that also > > > count as initialization? > > > > No. As I say, they're placed in the BSS. The BSS is zeroed as part of > > the C runtime initialisation. > > I don't understand the objection. With the above change, command_line[] > will end up consuming COMMAND_LINE_SIZE bytes of .data.init and will be > reliably initialized to all-zeros by the compiler (won't it?) > > > If you want to place a variable in a specific section, it must be > > explicitly initialised. Eg, > > > > static char __initdata command_line[COMMAND_LINE_SIZE] = ""; > > > > However, there is a bigger question here: that is the tradeoff between > > making this variable part of the on-disk kernel image, but throw away > > the memory at runtime, or to leave it in the BSS where it will not be > > part of the on-disk kernel image, but will not be thrown away at > > runtime. > > Yes, it'll take some space in vmlinux. We could perhaps create a new > __initbss to prevent that, I assume. > > - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/