linux-kernel - Re: [PATCH 6/13] maps: Move the page walker code to 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]

Date:	Thu, 05 Apr 2007 11:32:18 +1000
From:	Nick Piggin <nickpiggin@...oo.com.au>
To:	Matt Mackall <mpm@...enic.com>
CC:	Andrew Morton <akpm@...ux-foundation.org>,
	linux-kernel@...r.kernel.org
Subject: Re: [PATCH 6/13] maps: Move the page walker code to lib/

Matt Mackall wrote:
> On Wed, Apr 04, 2007 at 03:50:56PM +1000, Nick Piggin wrote:
> 
>>Matt Mackall wrote:
>>
>>>On Wed, Apr 04, 2007 at 01:51:37PM +1000, Nick Piggin wrote:
>>>
>>>
>>>>Matt Mackall wrote:
>>>>
>>>>
>>>>>Move the page walker code to lib/
>>>>>
>>>>>This lets it get shared outside of proc/ and linked in only when
>>>>>needed.
>>>>
>>>>I think it would be better in mm/.
>>>
>>>
>>>I originally was looking at putting it in mm/memory.c and possibly
>>
>>Just put it in its own file in mm/ rather than its own file in lib.
>>lib should be for almost-standalone stuff, IMO (ie. only using basic
>>kernel functionality).
> 
> 
> Arguably that's what lib/ should be for, but it's currently largely

I disagree. There is code everywhere that exists to provide some
functionality via an API to other parts of the kernel. You don't
think mm/page_alloc.c should go in lib/?

> used to avoid linking in unused code without adding more hair to
> Kconfig. Which is what I'm trying to do here.

Well if you're doing a nice big reorganisation and jumble, then
why would you worry about a few lines in Kconfig?

>>Apart from these users outside mm/, I don't see much point in converting
>>things over. The page table walking API we have now is neat and simple.
>>It takes a few lines of code, but is it a big problem?
> 
> 
> I don't think it really qualifies as either neat or simple. It may be
> about as neat as walking a heterogenous tree with an inconsistent
> naming scheme can be, but it's still a headache. A maze of twisty
> little passages, all slightly different.

All page table range walking code should be the same.
It is a simple template to use to walk a range of ptes. It is
a headache outside mm/, sure, but not because of its incredible
complexity.

-- 
SUSE Labs, Novell Inc.
-
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/