linux-kernel - Re: [PATCH v2 2/3] bq2415x_charger: Use power

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, 2 Dec 2013 01:02:40 +0100
From:	Michael Trimarchi <michael@...rulasolutions.com>
To:	Anton Vorontsov <anton@...msg.org>
Cc:	Pali Rohár <pali.rohar@...il.com>,
	David Woodhouse <dwmw2@...radead.org>,
	Tony Lindgren <tony@...mide.com>,
	Russell King <linux@....linux.org.uk>,
	linux-kernel@...r.kernel.org,
	Linux OMAP Mailing List <linux-omap@...r.kernel.org>,
	freemangordon@....bg, aaro.koskinen@....fi, pavel@....cz
Subject: Re: [PATCH v2 2/3] bq2415x_charger: Use power_supply notifier for automode

Hi Anton

On Sun, Dec 1, 2013 at 11:37 PM, Anton Vorontsov <anton@...msg.org> wrote:
> On Mon, Nov 25, 2013 at 08:16:34PM +0100, Michael Trimarchi wrote:
> ...
>> >> So you can read this value without any type of synchronization
>> >> with the power_supply_core
>> >> and sysfs implementation?
> ...
>> https://lists.ubuntu.com/archives/kernel-team/2013-January/025206.html
>>
>> I found and equivalent scenario that I was trying to said
>
> That's a good question, actually. Even though in Pali's case the notifier
> is atomic (so that we are pretty confident that the object won't be
> unregistered), there is still a possiblity of a dead lock, for example. So

So if the get_property is a sleeping function it will be a deadlock. Right?

Michael

> notifiers should be careful to not hold any locks, because the other
> driver might call get_property(), which might acquire locks.
>
> Thanks,
>
> Anton
--
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/