linux-kernel - Re: Null suspend/resume functions

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: <200911162007.11963.rjw@sisk.pl>
Date:	Mon, 16 Nov 2009 20:07:11 +0100
From:	"Rafael J. Wysocki" <rjw@...k.pl>
To:	Mark Brown <broonie@...nsource.wolfsonmicro.com>
Cc:	Kuninori Morimoto <morimoto.kuninori@...esas.com>,
	alsa-devel@...a-project.org, linux-pm@...ts.linux-foundation.org,
	Magnus Damm <damm@...nsource.se>, linux-kernel@...r.kernel.org
Subject: Re: Null suspend/resume functions

On Monday 16 November 2009, Mark Brown wrote:
> On Mon, Nov 09, 2009 at 01:31:36PM +0000, Mark Brown wrote:
> > On Mon, Nov 09, 2009 at 10:58:58AM +0000, Mark Brown wrote:
> > > On Mon, Nov 09, 2009 at 11:54:47AM +0900, Kuninori Morimoto wrote:
> 
> Any chance someone from the PM side could comment on the issue below?

There is.  I haven't had a chance to look at it yet, will do shortly.

> > > > +static int fsi_runtime_nop(struct device *dev)
> > > > +{
> > > > +	/* Runtime PM callback shared between ->runtime_suspend()
> > > > +	 * and ->runtime_resume(). Simply returns success.
> > > > +	 *
> > > > +	 * This driver re-initializes all registers after
> > > > +	 * pm_runtime_get_sync() anyway so there is no need
> > > > +	 * to save and restore registers here.
> > > > +	 */
> > > > +	return 0;
> > > > +}
> > > 
> > > This sets off alarm bells but it's perfectly reasonable, especially with
> > > platforms able to put things into a low power state with no explicit
> > > driver code now they can do power domain style things like SH.  I've
> > > CCed in the PM folks since this seems like a perfectly reasonable use
> > > case which ought to be handled more nicely.

Thanks,
Rafael
--
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/