From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Michael Grzeschik , Vinod Koul , Jonghwan Choi Subject: [ 095/110] dmaengine: imx-dma: fix callback path in tasklet Date: Fri, 11 Oct 2013 12:39:15 -0700 Message-Id: <20131011193818.156266702@linuxfoundation.org> In-Reply-To: <20131011193807.584188672@linuxfoundation.org> References: <20131011193807.584188672@linuxfoundation.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Michael Grzeschik commit fcaaba6c7136fe47e5a13352f99a64b019b6d2c5 upstream. We need to free the ld_active list head before jumping into the callback routine. Otherwise the callback could run into issue_pending and change our ld_active list head we just going to free. This will run the channel list into an currupted and undefined state. Signed-off-by: Michael Grzeschik Signed-off-by: Vinod Koul Cc: Jonghwan Choi Signed-off-by: Greg Kroah-Hartman --- drivers/dma/imx-dma.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) --- a/drivers/dma/imx-dma.c +++ b/drivers/dma/imx-dma.c @@ -604,13 +604,11 @@ static void imxdma_tasklet(unsigned long if (list_empty(&imxdmac->ld_active)) { /* Someone might have called terminate all */ - goto out; + spin_unlock_irqrestore(&imxdma->lock, flags); + return; } desc = list_first_entry(&imxdmac->ld_active, struct imxdma_desc, node); - if (desc->desc.callback) - desc->desc.callback(desc->desc.callback_param); - /* If we are dealing with a cyclic descriptor, keep it on ld_active * and dont mark the descriptor as complete. * Only in non-cyclic cases it would be marked as complete @@ -638,6 +636,10 @@ static void imxdma_tasklet(unsigned long } out: spin_unlock_irqrestore(&imxdma->lock, flags); + + if (desc->desc.callback) + desc->desc.callback(desc->desc.callback_param); + } static int imxdma_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,