From mboxrd@z Thu Jan  1 00:00:00 1970
From: Denys Vlasenko <vda.linux@googlemail.com>
Subject: Re: Testing of function/data-sections on linux-2.6.35-rc4
Date: Mon, 26 Jul 2010 03:31:34 +0200
Message-ID: <201007260331.34372.vda.linux@googlemail.com>
References: <201007181703.17022.vda.linux@googlemail.com> <20100723203543.GB27288@merkur.ravnborg.org>
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Cc: Tim Abbott <tabbott@ksplice.com>, Tim Bird <tim.bird@am.sony.com>,
	James Bottomley <James.Bottomley@hansenpartnership.com>,
	linux-kernel@vger.kernel.org,
	Matt Fleming <matt@console-pimps.org>,
	linux-arch@vger.kernel.org, Arnd Bergmann <arnd@arndb.de>,
	Michal Marek <mmarek@suse.cz>,
	Parisc List <linux-parisc@vger.kernel.org>
To: Sam Ravnborg <sam@ravnborg.org>
Return-path: <linux-arch-owner@vger.kernel.org>
In-Reply-To: <20100723203543.GB27288@merkur.ravnborg.org>
List-ID: <linux-arch.vger.kernel.org>
List-Id: linux-parisc.vger.kernel.org

Hi Sam,

On Friday 23 July 2010 22:35, Sam Ravnborg wrote:
> > 
> > Then, in order to also garbage-collect the sections, I added
> > 
> > LDFLAGS_vmlinux += --gc-sections
> > 
> > in top-level Makefile.
> > 
> > This requires the additional patch (linux-2.6.35-rc4-fsgs.patch)
> > which adds KEEP(section) directives to kernel linker stripts.
> > Otherwise, linker will discard some crucial sections.
> > 
> 
> Changelog does not address why you need:
> 
>      -Map $@.ldmap
> 
> and what effect they have.

I didn't plan to push the last step (--gc-sections) to mainline yet.
Thus the patch has debugging stuff in it.


> And it is obvious that some archs should consolidate a little more from
> asm-generic/vmlinux.lds.h.
> But that said this patch looks much better than the initial versions posted.
> 
> How do you determine which sections needs the KEEP()?
> Worth documenting for future when we add new sections.

No problem, I will be adding comments at every KEEP() why it's needed.

-- 
vda