[PATCH 1/1] dmaengine: fsl-edma: fix miss mutex unlock at an error return path

[PATCH 1/1] dmaengine: fsl-edma: fix miss mutex unlock at an error return path

[Frank Li]

Use cleanup to manage mutex. Let compiler to do scope guard automatically.

Fixes: 6aa60f79e679 ("dmaengine: fsl-edma: add safety check for 'srcid'")
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/r/202404110915.riwV3ZAC-lkp@intel.com/
Signed-off-by: Frank Li <Frank.Li@nxp.com>
---
 drivers/dma/fsl-edma-common.c | 1 +
 drivers/dma/fsl-edma-main.c   | 5 ++---
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/dma/fsl-edma-common.c b/drivers/dma/fsl-edma-common.c
index f9144b0154396..73628eac8aadc 100644
--- a/drivers/dma/fsl-edma-common.c
+++ b/drivers/dma/fsl-edma-common.c
@@ -3,6 +3,7 @@
 // Copyright (c) 2013-2014 Freescale Semiconductor, Inc
 // Copyright (c) 2017 Sysam, Angelo Dureghello  <angelo@sysam.it>
 
+#include <linux/cleanup.h>
 #include <linux/clk.h>
 #include <linux/dmapool.h>
 #include <linux/module.h>
diff --git a/drivers/dma/fsl-edma-main.c b/drivers/dma/fsl-edma-main.c
index 755a3dc3b0a78..de03148aed0b3 100644
--- a/drivers/dma/fsl-edma-main.c
+++ b/drivers/dma/fsl-edma-main.c
@@ -105,7 +105,8 @@ static struct dma_chan *fsl_edma_xlate(struct of_phandle_args *dma_spec,
 	if (dma_spec->args_count != 2)
 		return NULL;
 
-	mutex_lock(&fsl_edma->fsl_edma_mutex);
+	guard(mutex)(&fsl_edma->fsl_edma_mutex);
+
 	list_for_each_entry_safe(chan, _chan, &fsl_edma->dma_dev.channels, device_node) {
 		if (chan->client_count)
 			continue;
@@ -124,12 +125,10 @@ static struct dma_chan *fsl_edma_xlate(struct of_phandle_args *dma_spec,
 
 				fsl_edma_chan_mux(fsl_chan, fsl_chan->srcid,
 						true);
-				mutex_unlock(&fsl_edma->fsl_edma_mutex);
 				return chan;
 			}
 		}
 	}
-	mutex_unlock(&fsl_edma->fsl_edma_mutex);
 	return NULL;
 }
 
-- 
2.34.1

Re: [PATCH 1/1] dmaengine: fsl-edma: fix miss mutex unlock at an error return path

[Vinod Koul]

On Thu, 11 Apr 2024 16:39:35 -0400, Frank Li wrote:
> Use cleanup to manage mutex. Let compiler to do scope guard automatically.
> 
> 

Applied, thanks!

[1/1] dmaengine: fsl-edma: fix miss mutex unlock at an error return path
      commit: b52e28eca7da47fa389605a8eda1952a9fa3c69f

Best regards,
-- 
~Vinod