From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from bombadil.infradead.org ([18.85.46.34]:56611 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751301AbZLSKQE (ORCPT ); Sat, 19 Dec 2009 05:16:04 -0500 Message-ID: <4B2CA7B6.1000405@infradead.org> Date: Sat, 19 Dec 2009 08:15:18 -0200 From: Mauro Carvalho Chehab MIME-Version: 1.0 To: Andy Walls CC: Stefani Seibold , linux-kernel@vger.kernel.org, Andrew Morton , Linux Media Mailing List Subject: Re: [patch] media video cx23888 driver: fix possible races using new kfifo_API kfifo_reset() References: <1261174870.13019.24.camel@wall-e> <1261179828.3060.15.camel@palomino.walls.org> In-Reply-To: <1261179828.3060.15.camel@palomino.walls.org> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-media-owner@vger.kernel.org List-ID: Em 18-12-2009 21:43, Andy Walls escreveu: > On Fri, 2009-12-18 at 23:21 +0100, Stefani Seibold wrote: >> Fix the cx23888 driver to use the new kfifo API. Using kfifo_reset() may >> result in a possible race conditions. This patch fix it by using >> spinlock around the kfifo_reset() function. >> >> The patch-set is against mm tree from 11-Dec-2009 >> >> Greetings, >> Stefani >> >> Signed-off-by: Stefani Seibold > > For both this patch together with your previous patch: > > Reviewed-by: Andy Walls > Acked-by: Andy Walls Acked-by: Mauro Carvalho Chehab > > Thanks Stefani. > > Regards, > Andy > >> --- >> cx23888-ir.c | 9 +++++++++ >> 1 file changed, 9 insertions(+) >> >> --- mmotm.orig/drivers/media/video/cx23885/cx23888-ir.c 2009-12-18 22:57:13.588337402 +0100 >> +++ mmotm/drivers/media/video/cx23885/cx23888-ir.c 2009-12-18 23:15:14.651365720 +0100 >> @@ -519,6 +519,7 @@ static int cx23888_ir_irq_handler(struct >> { >> struct cx23888_ir_state *state = to_state(sd); >> struct cx23885_dev *dev = state->dev; >> + unsigned long flags; >> >> u32 cntrl = cx23888_ir_read4(dev, CX23888_IR_CNTRL_REG); >> u32 irqen = cx23888_ir_read4(dev, CX23888_IR_IRQEN_REG); >> @@ -629,8 +630,11 @@ static int cx23888_ir_irq_handler(struct >> cx23888_ir_write4(dev, CX23888_IR_CNTRL_REG, cntrl); >> *handled = true; >> } >> + >> + spin_lock_irqsave(&state->rx_kfifo_lock, flags); >> if (kfifo_len(&state->rx_kfifo) >= CX23888_IR_RX_KFIFO_SIZE / 2) >> events |= V4L2_SUBDEV_IR_RX_FIFO_SERVICE_REQ; >> + spin_unlock_irqrestore(&state->rx_kfifo_lock, flags); >> >> if (events) >> v4l2_subdev_notify(sd, V4L2_SUBDEV_IR_RX_NOTIFY, &events); >> @@ -783,7 +787,12 @@ static int cx23888_ir_rx_s_parameters(st >> o->interrupt_enable = p->interrupt_enable; >> o->enable = p->enable; >> if (p->enable) { >> + unsigned long flags; >> + >> + spin_lock_irqsave(&state->rx_kfifo_lock, flags); >> kfifo_reset(&state->rx_kfifo); >> + /* reset tx_fifo too if there is one... */ >> + spin_unlock_irqrestore(&state->rx_kfifo_lock, flags); >> if (p->interrupt_enable) >> irqenable_rx(dev, IRQEN_RSE | IRQEN_RTE | IRQEN_ROE); >> control_rx_enable(dev, p->enable); >> >> > > -- > To unsubscribe from this list: send the line "unsubscribe linux-media" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html