linux-kernel - Re: [RFC PATCH 1/2] regmap: add configurable lock class key for lockdep

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:	Mon, 29 Jun 2015 07:35:20 -0700
From:	Arjan van de Ven <arjan@...ux.intel.com>
To:	Mark Brown <broonie@...nel.org>,
	Nicolas Boichat <drinkcat@...omium.org>
CC:	Lars-Peter Clausen <lars@...afoo.de>,
	Mauro Carvalho Chehab <mchehab@....samsung.com>,
	Antti Palosaari <crope@....fi>, Ingo Molnar <mingo@...hat.com>,
	Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
	linux-kernel@...r.kernel.org, Bard Liao <bardliao@...ltek.com>,
	Oder Chiou <oder_chiou@...ltek.com>,
	Liam Girdwood <lgirdwood@...il.com>,
	Jaroslav Kysela <perex@...ex.cz>, Takashi Iwai <tiwai@...e.de>,
	alsa-devel@...a-project.org,
	Anatol Pomozov <anatol.pomozov@...il.com>
Subject: Re: [RFC PATCH 1/2] regmap: add configurable lock class key for lockdep

On 6/29/2015 7:22 AM, Mark Brown wrote:
> On Mon, Jun 29, 2015 at 10:03:09PM +0800, Nicolas Boichat wrote:
>
>> regmap instances are kalloc'ed, so they cannot contain the
>> lock_class_key, which needs to be statically allocated (in .data).
>> Another option would be to preallocate a bunch of lock_class_key in
>> regmap.c, and pick from that, but that's terribly hacky...
>
> Honestly this is all starting to sound like we're having to jump through
> too many hoops for lockep (and other APIs are too from the sounds of it)
> so we should be looking at lockdep here.

lockdep assumes that there is a known lock hierarchy, at least known
to the developer.

seems like for regmap there isn't

(I would be interested to know how you avoid ABBA deadlocks btw,
can you have 2 devices, one with a hierarchy one way, and another
with the hierarchy the other way?)


--
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/