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Date: Fri, 17 Feb 2017 10:42:42 -0800
From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: Lucas Stach <l.stach@pengutronix.de>
Cc: linux-kernel@vger.kernel.org, patchwork-lst@pengutronix.de,
        kernel@pengutronix.de
Subject: Re: [PATCH] driver core: unbind consumers before locking parent on
 device unbind
Message-ID: <20170217184242.GA11935@kroah.com>
References: <20170217183629.3628-1-l.stach@pengutronix.de>
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On Fri, Feb 17, 2017 at 07:36:29PM +0100, Lucas Stach wrote:
> On forced unbind the parent lock is taken, as the device might be a USB
> device. The device to be unbound might have active consumers, which
> must be unbound before calling device_release_driver(), otherwise this
> function might deadlock when trying to take the parent lock during
> consumer unbind.

Really?  What type of device does this fail on today?

thanks,

greg k-h