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Date: Thu, 3 Aug 2017 10:50:18 +0800
From: Shawn Guo <shawnguo@kernel.org>
To: Stefan Agner <stefan@agner.ch>
Cc: kernel@pengutronix.de, Fabio Estevam <fabio.estevam@nxp.com>,
        Andrey Smirnov <andrew.smirnov@gmail.com>,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] soc: imx: gpcv2: fix regulator deferred probe
Message-ID: <20170803025017.GJ31819@dragon>
References: <20170802195129.20442-1-stefan@agner.ch>
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On Wed, Aug 02, 2017 at 12:51:29PM -0700, Stefan Agner wrote:
> If a regulator requests a deferred probe, the power domain gets
> initialized twice. This leads to a list double add (without
> list debugging the kernel hangs due to the double add later):
> 
>   WARNING: CPU: 0 PID: 19 at lib/list_debug.c:31 __list_add_valid+0xbc/0xc4
>   list_add double add: new=c1229754, prev=c12383b4, next=c1229754.
> 
> Initialize the power domain after we get the regulator. Also do
> not print an error in case the regulator defers probing.
> 
> Cc: Fabio Estevam <fabio.estevam@nxp.com>
> Cc: Andrey Smirnov <andrew.smirnov@gmail.com>
> Cc: linux-arm-kernel@lists.infradead.org
> Cc: linux-kernel@vger.kernel.org
> Fixes: 03aa12629fc4 ("soc: imx: Add GPCv2 power gating driver")
> Signed-off-by: Stefan Agner <stefan@agner.ch>
> ---
> Hi Shawn,
> 
> Since this leads to a Kernel hang in v4.13-rc3, can you get this
> into v4.13 still?

Sure.  But before doing that, I would like to get an ACK from Andrey on
this fix.

Shawn