Re: w1: 3.14-rc7 - possible recursive locking detected

[David Fries <David@Fries.net>]

On Mon, Mar 17, 2014 at 10:38:13PM +0100, Belisko Marek wrote:
> Hi,
> 
> booting latest 3.14-rc7 on gta04 board gives following warning:
> 
> [    3.101409] Driver for 1-wire Dallas network protocol.
> [    3.109649] omap_hdq omap_hdq: OMAP HDQ Hardware Rev 0.5. Driver in
> [    3.400146]        CPU0
> [    3.402709]        ----
> [    3.405273]   lock(&(&priv->bus_notifier)->rwsem);
> [    3.410308]   lock(&(&priv->bus_notifier)->rwsem);
> [    3.415374]
> [    3.415374]  *** DEADLOCK ***
> 
> AFAIK we didn't see that on (at least 3/14-rc2).

The last drivers/w1 change went in before v3.14-rc1, so if it is
something in the w1 code, it has either been there or something else
in the rest of the kernel changed to expose it.  I'm using the ds2490
USB w1 dongle, I didn't see that problem when enabling lock debugging
on 3.14.0-rc5+ which includes some changes I'm working on.

https://github.com/dfries/linux.git w1_rework

-- 
David Fries <david@fries.net>    PGP pub CB1EE8F0
http://fries.net/~david/