On Wed, Aug 12, 2020 at 06:37:59AM +0800, kernel test robot wrote:
> tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
> master
> head: c636eef2ee3696f261a35f34989842701a107895
> commit: 7cbb0c63de3fc218fd06ecfedb477772a4d12f76 dmaengine: xilinx: dpdma:
> Add the Xilinx DisplayPort DMA engine driver
> date: 4 weeks ago
> config: h8300-randconfig-m031-20200811 (attached as .config)
> compiler: h8300-linux-gcc (GCC) 9.3.0
>
> If you fix the issue, kindly add following tag as appropriate
> Reported-by: kernel test robot <[email protected]>
>
> smatch warnings:
> drivers/dma/xilinx/xilinx_dpdma.c:1172 xilinx_dpdma_synchronize() error:
> double unlocked 'chan->vchan.lock' (orig line 1170)
Unless I'm mistaken, this is a false positive. I'd appreciate if someone
could check if I'm missing something obvious.
> vim +1172 drivers/dma/xilinx/xilinx_dpdma.c
>
> 1140
> 1141 /**
> 1142 * xilinx_dpdma_synchronize - Synchronize callback execution
> 1143 * @dchan: DMA channel
> 1144 *
> 1145 * Synchronizing callback execution ensures that all previously
> issued
> 1146 * transfers have completed and all associated callbacks have
> been called and
> 1147 * have returned.
> 1148 *
> 1149 * This function waits for the DMA channel to stop. It assumes
> it has been
> 1150 * paused by a previous call to dmaengine_terminate_async(),
> and that no new
> 1151 * pending descriptors have been issued with
> dma_async_issue_pending(). The
> 1152 * behaviour is undefined otherwise.
> 1153 */
> 1154 static void xilinx_dpdma_synchronize(struct dma_chan *dchan)
> 1155 {
> 1156 struct xilinx_dpdma_chan *chan = to_xilinx_chan(dchan);
> 1157 unsigned long flags;
> 1158
> 1159 xilinx_dpdma_chan_stop(chan);
> 1160
> 1161 spin_lock_irqsave(&chan->vchan.lock, flags);
> 1162 if (chan->desc.pending) {
> 1163
> vchan_terminate_vdesc(&chan->desc.pending->vdesc);
> 1164 chan->desc.pending = NULL;
> 1165 }
> 1166 if (chan->desc.active) {
> 1167
> vchan_terminate_vdesc(&chan->desc.active->vdesc);
> 1168 chan->desc.active = NULL;
> 1169 }
> > 1170 spin_unlock_irqrestore(&chan->vchan.lock, flags);
> 1171
> > 1172 vchan_synchronize(&chan->vchan);
> 1173 }
> 1174
>
--
Regards,
Laurent Pinchart
