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Date:   Fri, 25 Jan 2019 10:44:12 -0600
From:   Bin Liu <b-liu@ti.com>
To:     "Matwey V. Kornilov" <matwey.kornilov@gmail.com>
CC:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        "open list:MUSB MULTIPOINT HIGH SPEED DUAL-ROLE CONTROLLER" 
        <linux-usb@vger.kernel.org>,
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Subject: Re: [PATCH] usb: musb: Fix potential NULL dereference
Message-ID: <20190125164412.GJ18982@uda0271908>
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        "Matwey V. Kornilov" <matwey.kornilov@gmail.com>,
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On Thu, Jan 24, 2019 at 09:47:02PM +0300, Matwey V. Kornilov wrote:
> By the way, why do we need to store the qh in urb->hcpriv?
> qh can always be accessible through urb->ep->hcpriv
> Wouldn't it be better to drop entire urb->hcpriv usage?

I am not sure why. The code is there since the first commit in a decade
ago. But I tend to agree with you.

In a quick search for urb->hcpriv and urb->ep->hcpriv, based on the
usage in core/hcd.c, it seems to me that urb->hcpriv should not be
changed in each controller driver, but I see both have been used in most
controller drivers. I will leave this to others to educate me.

Regards,
-Bin.