linux-kernel - Re: [PATCH] Allow linker to eliminate unused functions in lib/*

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20100111142412.GA28783@one.firstfloor.org>
Date:	Mon, 11 Jan 2010 15:24:12 +0100
From:	Andi Kleen <andi@...stfloor.org>
To:	Dave Chinner <david@...morbit.com>
Cc:	Andi Kleen <andi@...stfloor.org>,
	Andrew Morton <akpm@...ux-foundation.org>,
	linux-kernel@...r.kernel.org
Subject: Re: [PATCH] Allow linker to eliminate unused functions in lib/*

On Mon, Jan 11, 2010 at 10:17:08AM +1100, Dave Chinner wrote:
> On Sat, Jan 09, 2010 at 05:51:56PM +0100, Andi Kleen wrote:
> > > Sneaky.
> > > 
> > > It's a bit sad to reduce the code cleanliness and maintainability in
> > > this way, but 1k is 1k.
> > 
> > Yes. I had actually hoped for more too. I think it might bring 
> > more with -ffunction-sections/--gc-sections, but I haven't tried that.
> > 
> > An alternative might be also to give some more of those explicit Kconfig
> > symbols -- then kernels with module loading enabled would benefit more
> > too -- but I haven't investigated how many changes that would need.
> > 
> > But even with that it's a reasonable improvement and putting the exports
> > separately is not too bad.
> > 
> > > The patch assumes a pre-existing lib-syms.c.  Confused.
> > 
> > Sorry, some day I'll learn how to operate quilt properly.
> > 
> > Updated patch with all files included appended.
> 
> Andi, how do you want to handle the overlap between this and the
> list_sort() patch I sent? I'm going to need a list_sort() available
> in the XFS tree well before the 2.6.34 merge window....

Shouldn't be difficult to merge, it's just a few lines. Someone will
do that.

It wou;ld be better if you put it into a separate file like I suggested
earlier though, then the list_sort() could be actually eliminated when
not needed.

-Andi
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/