From mboxrd@z Thu Jan  1 00:00:00 1970
From: Takashi Iwai <tiwai@suse.de>
Subject: Re: [PATCH 2/5] ALSA: snd-usb: implement new
	endpoint	streaming model
Date: Tue, 20 Dec 2011 16:42:58 +0100
Message-ID: <s5hehvzgsfx.wl%tiwai@suse.de>
References: <1324374520-32332-1-git-send-email-zonque@gmail.com>
	<1324374520-32332-3-git-send-email-zonque@gmail.com>
Mime-Version: 1.0 (generated by SEMI 1.14.6 - "Maruoka")
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: 7bit
Return-path: <alsa-devel-bounces@alsa-project.org>
Received: from mx2.suse.de (cantor2.suse.de [195.135.220.15])
	by alsa0.perex.cz (Postfix) with ESMTP id 326F0103B55
	for <alsa-devel@alsa-project.org>; Tue, 20 Dec 2011 16:43:01 +0100 (CET)
In-Reply-To: <1324374520-32332-3-git-send-email-zonque@gmail.com>
List-Unsubscribe: <http://mailman.alsa-project.org/mailman/listinfo/alsa-devel>,
	<mailto:alsa-devel-request@alsa-project.org?subject=unsubscribe>
List-Archive: <http://mailman.alsa-project.org/pipermail/alsa-devel>
List-Post: <mailto:alsa-devel@alsa-project.org>
List-Help: <mailto:alsa-devel-request@alsa-project.org?subject=help>
List-Subscribe: <http://mailman.alsa-project.org/mailman/listinfo/alsa-devel>,
	<mailto:alsa-devel-request@alsa-project.org?subject=subscribe>
Sender: alsa-devel-bounces@alsa-project.org
Errors-To: alsa-devel-bounces@alsa-project.org
To: Daniel Mack <zonque@gmail.com>
Cc: blablack@gmail.com, alsa-devel@alsa-project.org, clemens@ladisch.de, gdiffey@gmail.com, linuxaudio@showlabor.de
List-Id: alsa-devel@alsa-project.org

At Tue, 20 Dec 2011 10:48:37 +0100,
Daniel Mack wrote:
> 
> @@ -99,7 +104,7 @@ static int deactivate_urbs(struct snd_usb_substream *subs, int force, int can_sl
>   */
>  static void release_urb_ctx(struct snd_urb_ctx *u)
>  {
> -	if (u->urb) {
> +	if (!u || u->urb) {
>  		if (u->buffer_size)

This will lead to Oops when u == NULL, no?


> +/* determine the number of frames in the next packet */
> +static int next_packet_size(struct snd_usb_endpoint *ep)
> +{
> +	unsigned long flags;
> +
> +	if (ep->fill_max)
> +		return ep->maxframesize;
> +
> +	spin_lock_irqsave(&ep->lock, flags);
> +	ep->phase = (ep->phase & 0xffff)
> +		+ (ep->freqm << ep->datainterval);
> +	spin_unlock_irqrestore(&ep->lock, flags);
> +
> +	return min(ep->phase >> 16, ep->maxframesize);

If you need a protection here, safer to cover until min(), I guess.


Takashi