From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from userp1040.oracle.com ([156.151.31.81]:40898 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754182Ab3LPPGk (ORCPT ); Mon, 16 Dec 2013 10:06:40 -0500 Date: Mon, 16 Dec 2013 18:06:12 +0300 From: Dan Carpenter To: Mauro Carvalho Chehab Cc: Greg Kroah-Hartman , Laurent Pinchart , Hans Verkuil , Sergio Aguirre , linux-media@vger.kernel.org, devel@driverdev.osuosl.org, kernel-janitors@vger.kernel.org Subject: [media] v4l: omap4iss: Restore irq flags correctly in omap4iss_video_buffer_next() Message-ID: <20131216150612.GA15506@elgon.mountain> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Sender: linux-media-owner@vger.kernel.org List-ID: The spin_lock_irqsave() macro is not nestable. The second call will overwrite the first record of "flags" so the IRQs will not be enabled correctly at the end of the function. I haven't looked at all the callers but it could be that this function is always called with interrupts disabled and the bug doesn't cause problems in real life. Signed-off-by: Dan Carpenter diff --git a/drivers/staging/media/omap4iss/iss_video.c b/drivers/staging/media/omap4iss/iss_video.c index 766491e6a8d0..c9b71c750b15 100644 --- a/drivers/staging/media/omap4iss/iss_video.c +++ b/drivers/staging/media/omap4iss/iss_video.c @@ -451,9 +451,9 @@ struct iss_buffer *omap4iss_video_buffer_next(struct iss_video *video) } if (video->type == V4L2_BUF_TYPE_VIDEO_CAPTURE && pipe->input != NULL) { - spin_lock_irqsave(&pipe->lock, flags); + spin_lock(&pipe->lock); pipe->state &= ~ISS_PIPELINE_STREAM; - spin_unlock_irqrestore(&pipe->lock, flags); + spin_unlock(&pipe->lock); } buf = list_first_entry(&video->dmaqueue, struct iss_buffer,