linux-kernel - Re: [RFC PATCH v2 1/3] PM / Core: suspend

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 for Android: free password hash cracker in your pocket

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

Message-Id: <201104262249.22564.rjw@sisk.pl>
Date:	Tue, 26 Apr 2011 22:49:22 +0200
From:	"Rafael J. Wysocki" <rjw@...k.pl>
To:	Pavel Machek <pavel@....cz>
Cc:	Greg KH <gregkh@...e.de>, MyungJoo Ham <myungjoo.ham@...sung.com>,
	linux-pm@...ts.linux-foundation.org,
	Len Brown <len.brown@...el.com>,
	"Jean Delvare (PC drivers core)" <khali@...ux-fr.org>,
	"Ben Dooks (embedded platforms)" <ben-linux@...ff.org>,
	kyungmin.park@...sung.com, myungjoo.ham@...il.com,
	LKML <linux-kernel@...r.kernel.org>,
	Alan Stern <stern@...land.harvard.edu>
Subject: Re: [RFC PATCH v2 1/3] PM / Core: suspend_again callback for device PM.

On Tuesday, April 26, 2011, Pavel Machek wrote:
> Hi!
> 
> > > To conclude, I'm not sure about the approach.  In particular, I'm not sure
> > > if the benefit is worth the effort and the resulting complications (ie. the
> > > possibility of having to deal with wakeup signals not requested by user
> > > space) seem to be a bit too far reaching.
> > > 
> > > Greg, what do you think?
> > 
> > I agree with you in that I don't think that this type of feature is
> > valid at the moment.
> 
> Our current "solution" is low level suspend code on Zaurus directly
> looking at charger state and doing the "wakeup or not" decision by hand. 
> 
> > I don't understand why our current situation doesn't work, what are we
> > lacking that is needed for these systems that we have not seen
> > before?
> 
> It works, but it is ugly; and it seems samsung now needs similar
> hacks.
> 
> > What is the root problem that this is trying to solve?
> 
> It is trying to fix machines that need to run periodic kernel tasks
> even when user asked them to sleep. Zaurus needs to periodicaly wake
> up to be able to charge battery in s2ram state, for example.

Well, if you wake up periodically, it's not S2RAM any more, I'd say.

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/