linux-kernel - Re: [PATCH 0/8] Suspend block api (version 7)

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: <201005172344.46222.rjw@sisk.pl>
Date:	Mon, 17 May 2010 23:44:46 +0200
From:	"Rafael J. Wysocki" <rjw@...k.pl>
To:	Brian Swetland <swetland@...gle.com>
Cc:	Arve Hjønnevåg <arve@...roid.com>,
	linux-pm@...ts.linux-foundation.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH 0/8] Suspend block api (version 7)

On Monday 17 May 2010, Brian Swetland wrote:
> On Mon, May 17, 2010 at 1:40 PM, Rafael J. Wysocki <rjw@...k.pl> wrote:
> > On Monday 17 May 2010, Arve Hjønnevåg wrote:
> >>
> >> It should get out of that loop as soon as someone blocks suspend. If
> >> someone is constantly aborting suspend without using a suspend blocker
> >> it will be very inefficient, but it should still work.
> >
> > Well, the scenario I have in mind is the following.  Someone wants to check
> > the feature and simply writes "opportunistic" to /sys/power/policy and "mem" to
> > /sys/power/state without any drivers or apps that use suspend blockers.
> >
> > How in that case is the system supposed to break out of the suspend-resume loop
> > resulting from this?  I don't see right now, because the main blocker is
> > inactive, there are no other blockers that can be activated and it is next to
> > impossible to write to /sys/power/state again.
> 
> I guess we could set a flag when a suspend blocker is registered and
> refuse to enter opportunistic mode if no blockers have ever been
> registered.
> 
> It does seem like extra effort to go through to handle a "don't do
> that" type scenario (entering into opportunistic suspend without
> anything that will prevent it).

I agree, but I think it's necessary.  We shouldn't add interfaces that hurt
users if not used with care.

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/