Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751990AbaBGJRa (ORCPT ); Fri, 7 Feb 2014 04:17:30 -0500 Received: from smtp-vbr9.xs4all.nl ([194.109.24.29]:2401 "EHLO smtp-vbr9.xs4all.nl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750868AbaBGJR1 (ORCPT ); Fri, 7 Feb 2014 04:17:27 -0500 Message-ID: <52F4A486.30100@xs4all.nl> Date: Fri, 07 Feb 2014 10:16:54 +0100 From: Hans Verkuil User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20131103 Icedove/17.0.10 MIME-Version: 1.0 To: Arnd Bergmann CC: linux-kernel@vger.kernel.org, Mauro Carvalho Chehab , linux-media@vger.kernel.org Subject: Re: [PATCH, RFC 08/30] [media] arv: fix sleep_on race References: <1388664474-1710039-1-git-send-email-arnd@arndb.de> <1388664474-1710039-9-git-send-email-arnd@arndb.de> <52D90B42.90206@xs4all.nl> In-Reply-To: <52D90B42.90206@xs4all.nl> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 01/17/2014 11:51 AM, Hans Verkuil wrote: > On 01/02/2014 01:07 PM, Arnd Bergmann wrote: >> interruptible_sleep_on is racy and going away. In the arv driver that >> race has probably never caused problems since it would require a whole >> video frame to be captured before the read function has a chance to >> go to sleep, but using wait_event_interruptible lets us kill off the >> old interface. In order to do this, we have to slightly adapt the >> meaning of the ar->start_capture field to distinguish between not having >> started a frame and having completed it. >> >> Signed-off-by: Arnd Bergmann >> Cc: Mauro Carvalho Chehab >> Cc: linux-media@vger.kernel.org >> --- >> drivers/media/platform/arv.c | 4 ++-- >> 1 file changed, 2 insertions(+), 2 deletions(-) >> >> diff --git a/drivers/media/platform/arv.c b/drivers/media/platform/arv.c >> index e346d32d..32f6d70 100644 >> --- a/drivers/media/platform/arv.c >> +++ b/drivers/media/platform/arv.c >> @@ -307,11 +307,11 @@ static ssize_t ar_read(struct file *file, char *buf, size_t count, loff_t *ppos) >> /* >> * Okay, kick AR LSI to invoke an interrupt >> */ >> - ar->start_capture = 0; >> + ar->start_capture = -1; > > start_capture is defined as an unsigned. Can you make a new patch that changes > the type of start_capture to int? > > Otherwise it looks fine. ping! Regards, Hans -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/