Re: [PATCH] power: reset: at91-reset: free resources on exit path

[Nicolas Ferre]

On 09/02/2021 at 12:01, Claudiu Beznea wrote:
Free resources on exit path (failure path of probe and remove).

I'm not sure we can use this driver as a module anyway.

Otherwise, it looks fine, but isn't it possible to use devm_of_iomap(), 
even in loop, and avoid having to deal with exit path?

Reported-by: kernel test robot <l...@intel.com>
Reported-by: Dan Carpenter <dan.carpen...@oracle.com>
Signed-off-by: Claudiu Beznea <claudiu.bez...@microchip.com>
---
  drivers/power/reset/at91-reset.c | 25 ++++++++++++++++++++-----
  1 file changed, 20 insertions(+), 5 deletions(-)

diff --git a/drivers/power/reset/at91-reset.c b/drivers/power/reset/at91-reset.c
index 3ff9d93a5226..2ff7833153b6 100644
--- a/drivers/power/reset/at91-reset.c
+++ b/drivers/power/reset/at91-reset.c
@@ -206,7 +206,8 @@ static int __init at91_reset_probe(struct platform_device 
*pdev)
                        if (!reset->ramc_base[idx]) {
                                dev_err(&pdev->dev, "Could not map ram controller 
address\n");
                                of_node_put(np);
-                               return -ENODEV;
+                               ret = -ENODEV;
+                               goto unmap;
                        }
                        idx++;
                }
@@ -218,13 +219,15 @@ static int __init at91_reset_probe(struct platform_device 
*pdev)
        reset->args = (u32)match->data;
  
  	reset->sclk = devm_clk_get(&pdev->dev, NULL);
-       if (IS_ERR(reset->sclk))
-               return PTR_ERR(reset->sclk);
+       if (IS_ERR(reset->sclk)) {
+               ret = PTR_ERR(reset->sclk);
+               goto unmap;
+       }
  
  	ret = clk_prepare_enable(reset->sclk);
        if (ret) {
                dev_err(&pdev->dev, "Could not enable slow clock\n");
-               return ret;
+               goto unmap;
        }
  
  	platform_set_drvdata(pdev, reset);
@@ -239,21 +242,33 @@ static int __init at91_reset_probe(struct platform_device 
*pdev)
        ret = register_restart_handler(&reset->nb);
        if (ret) {
                clk_disable_unprepare(reset->sclk);
-               return ret;
+               goto unmap;
        }
  
  	at91_reset_status(pdev, reset->rstc_base);
  
  	return 0;
+
+unmap:
+       iounmap(reset->rstc_base);
+       for (idx = 0; idx < ARRAY_SIZE(reset->ramc_base); idx++)
+               iounmap(reset->ramc_base[idx]);

But if we keep this loop, I have the feeling that some kind of 
"of_node_put()" is needed as well.

+
+       return ret;
  }
  
  static int __exit at91_reset_remove(struct platform_device *pdev)
  {
        struct at91_reset *reset = platform_get_drvdata(pdev);
+       int idx;
  
  	unregister_restart_handler(&reset->nb);
        clk_disable_unprepare(reset->sclk);
  
+	iounmap(reset->rstc_base);
+       for (idx = 0; idx < ARRAY_SIZE(reset->ramc_base); idx++)
+               iounmap(reset->ramc_base[idx]);

Ditto

+
        return 0;
  }
  



--
Nicolas Ferre