Re: [PATCH] usb: cdnsp: Fix incorrect calling of cdnsp_died function

From: Peter Chen <peter.chen@kernel.org>
To: Pawel Laszczak <pawell@cadence.com>
Cc: gregkh@linuxfoundation.org, linux-usb@vger.kernel.org,
	linux-kernel@vger.kernel.org, jianhe@ambarella.com,
	stable@vger.kernel.org
Subject: Re: [PATCH] usb: cdnsp: Fix incorrect calling of cdnsp_died function
Date: Mon, 13 Dec 2021 21:13:18 +0800	[thread overview]
Message-ID: <20211213131318.GB5346@Peter> (raw)
In-Reply-To: <20211210112945.660-1-pawell@gli-login.cadence.com>

On 21-12-10 12:29:45, Pawel Laszczak wrote:
> From: Pawel Laszczak <pawell@cadence.com>
> 
> Patch restrict calling of cdnsp_died function during removing modules
> or software disconnect.
> This function was called because after transition controller to HALT
> state the driver starts handling the deferred interrupt.
> In this case such interrupt can be simple ignored.
> 
> Fixes: 3d82904559f4 ("usb: cdnsp: cdns3 Add main part of Cadence USBSSP DRD Driver")
> cc: <stable@vger.kernel.org>
> Signed-off-by: Pawel Laszczak <pawell@cadence.com>
> ---
>  drivers/usb/cdns3/cdnsp-ring.c | 9 ++++++++-
>  1 file changed, 8 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/usb/cdns3/cdnsp-ring.c b/drivers/usb/cdns3/cdnsp-ring.c
> index e8f5ecbb5c75..e45c3d6e1536 100644
> --- a/drivers/usb/cdns3/cdnsp-ring.c
> +++ b/drivers/usb/cdns3/cdnsp-ring.c
> @@ -1525,7 +1525,14 @@ irqreturn_t cdnsp_thread_irq_handler(int irq, void *data)
>  	spin_lock_irqsave(&pdev->lock, flags);
>  
>  	if (pdev->cdnsp_state & (CDNSP_STATE_HALTED | CDNSP_STATE_DYING)) {
> -		cdnsp_died(pdev);
> +		/*
> +		 * While removing or stopping driver there may still be deferred
> +		 * not handled interrupt which should not be treated as error.
> +		 * Driver should simply ignore it.
> +		 */
> +		if (pdev->gadget_driver)
> +			cdnsp_died(pdev);
> +

Reviewed-by: Peter Chen <peter.chen@kernel.org>

-- 

Thanks,
Peter Chen