linux-kernel - Re: [PATCH 2/2] platform: Facilitate the creation of pseudo-platform buses

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] [day] [month] [year] [list]

Message-ID: <87tyml1itn.fsf@deeprootsystems.com>
Date:	Mon, 23 Aug 2010 07:53:40 -0700
From:	Kevin Hilman <khilman@...prootsystems.com>
To:	Grant Likely <grant.likely@...retlab.ca>
Cc:	"Moffett\, Kyle D" <Kyle.D.Moffett@...ing.com>,
	Patrick Pannuto <ppannuto@...eaurora.org>,
	"linux-kernel\@vger.kernel.org" <linux-kernel@...r.kernel.org>,
	"linux-arm-msm\@vger.kernel.org" <linux-arm-msm@...r.kernel.org>,
	"magnus.damm\@gmail.com" <magnus.damm@...il.com>,
	"gregkh\@suse.de" <gregkh@...e.de>,
	Paul Mundt <lethal@...ux-sh.org>,
	Magnus Damm <damm@...nsource.se>,
	"Rafael J. Wysocki" <rjw@...k.pl>,
	Eric Miao <eric.y.miao@...il.com>,
	Dmitry Torokhov <dtor@...l.ru>,
	"netdev\@vger.kernel.org" <netdev@...r.kernel.org>,
	Kyle D Moffett <kyle@...fetthome.net>
Subject: Re: [PATCH 2/2] platform: Facilitate the creation of pseudo-platform buses

Grant Likely <grant.likely@...retlab.ca> writes:

>>> If the override is global to the platform_bus_type, then the model
>>> will not scale.
>>
>> It will not scale any more (or less) than the current functionality of
>> the driver model which handles this globally.  Again, if scalabilty
>> becomes a problem down the road, lets fix it then.
>
> Alright, I can agree to that.  I do agree that the runtime override is
> far and away better than the weak symbol approach.  However, there
> needs to be some very clear rules in place for users of the override,
> namely that users must understand that they are stewards of the
> platform_bus_type, and must take care to preserve the default
> behaviour for "uninteresting" devices.

Completely agree here.

Any overrides of the dev_pm_ops functions that do not also call the
pm_generic_* functions (or their equivalents) should be suspect.

I'll post a proposal for a runtime override shortly.

> Also, the expectation should be that it is a temporary measure until a
> better abstraction is implemented.  It might be that a separate
> bus_type is the way to go (if the multiple driver registration problem
> can be solved) or it might be a way to differentiate pm_ops either
> per-device or per-parent.  I'm not sure, but I'm starting on an OMAP
> project soon, so I may very well end up working on this.

Yes, I'll be glad to work on this too, but first I need to get through
reviewing the backlog of all the OMAP drivers we're converting to
runtime PM.

Kevin
--
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/