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Message-ID: <1584980402.27949.21.camel@suse.de>
Subject: Re: lockdep warning in urb.c:363 usb_submit_urb
From:   Oliver Neukum <oneukum@suse.de>
To:     Qais Yousef <qais.yousef@arm.com>
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org
Date:   Mon, 23 Mar 2020 17:20:02 +0100
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Am Montag, den 23.03.2020, 15:57 +0000 schrieb Qais Yousef:
> On 03/23/20 16:36, Oliver Neukum wrote:
> > Am Montag, den 23.03.2020, 14:38 +0000 schrieb Qais Yousef:
> > > Hi
> > > 
> > > I've hit the following lockdep warning when I trigger hibernate on arm64
> > > platform (Juno-r2)
> > > 
> > > 
> > > 	echo suspend > /sys/power/disk
> > > 	echo disk > /sys/power/state
> > > 
> > > I only had a usb flash drive attached to it. Let me know if you need more info.
> > 
> > Hi,
> > 
> > that is not a lockdep issue, but the hub driver is not properly killing
> > its URB presumably. Yet, the driver looks correct to me. Please use
> > the additional patch and activate dynamic debugging for usbcore.
> 
> Yes sorry my bad, it's a WARN_ONCE().
> 
> I applied your patch and will reproduce, but meanwhile not sure if you noticed
> this line in my previous email
> 
> [  327.154849] usb usb2: runtime PM trying to activate child device usb2 but parent (7ffb0000.ohci) is not active

Hi,

yes I noticed, but that did not trigger the WARN(). One thing at a time
please.

	Regards
		Oliver