From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
        id S938945AbcIERYU (ORCPT <rfc822;w@1wt.eu>);
        Mon, 5 Sep 2016 13:24:20 -0400
Received: from mail.pqgruber.com ([178.189.19.235]:50293 "EHLO
        mail.pqgruber.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
        with ESMTP id S934010AbcIERYQ (ORCPT
        <rfc822;linux-kernel@vger.kernel.org>);
        Mon, 5 Sep 2016 13:24:16 -0400
Date: Mon, 5 Sep 2016 19:24:05 +0200
From: Clemens Gruber <clemens.gruber@pqgruber.com>
To: Peter Chen <hzpeterchen@gmail.com>
Cc: linux-usb@vger.kernel.org,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        linux-kernel@vger.kernel.org
Subject: Re: chipidea: udc: kernel panic in isr_setup_status_phase
Message-ID: <20160905172405.GA2114@archie.localdomain>
References: <20160823003630.GA3052@archie.localdomain>
 <20160824081102.GA27233@shlinux2>
 <20160825234740.GA12850@archie.localdomain>
 <20160826172151.GA21360@b29397-desktop>
 <20160828181502.GA7785@archie.localdomain>
 <20160829102402.GA3736@b29397-desktop>
 <20160830172045.GA2634@archie.localdomain>
 <20160902015552.GE11262@shlinux2>
 <20160902164243.GA4549@archie.localdomain>
 <20160905031022.GC24593@b29397-desktop>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20160905031022.GC24593@b29397-desktop>
User-Agent: Mutt/1.7.0 (2016-08-17)
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

On Mon, Sep 05, 2016 at 11:10:22AM +0800, Peter Chen wrote:
> How about below, it will set halt for device, and host will get stall
> from the device.
> 
> diff --git a/drivers/usb/chipidea/udc.c b/drivers/usb/chipidea/udc.c
> index 0f692fc..3c46ccb 100644
> --- a/drivers/usb/chipidea/udc.c
> +++ b/drivers/usb/chipidea/udc.c
> @@ -946,6 +946,11 @@ static int isr_setup_status_phase(struct ci_hdrc *ci)
>  	int retval;
>  	struct ci_hw_ep *hwep;
>  
> +	if (!ci->status) {
> +		WARN_ON(1);
> +		return -EPIPE;
> +	}
> +
>  	hwep = (ci->ep0_dir == TX) ? ci->ep0out : ci->ep0in;
>  	ci->status->context = ci;
>  	ci->status->complete = isr_setup_status_complete;
> 

Returning -EPIPE works! I would however suggest to only warn once, as
this otherwise floods the kernel log.

I'll send a patch shortly, also adding a comment for people experiencing
a similar hardware problem.

Thank you very much for your help, Peter!

Regards,
Clemens