Re: [PATCH] clk: qcom: common: check for failure

From: Stephen Boyd
Date: Thu Dec 03 2015 - 02:39:23 EST


On 12/01, Sudip Mukherjee wrote:
> We were not checking the return from devm_add_action() which can fail.
>
> Signed-off-by: Sudip Mukherjee <sudip@xxxxxxxxxxxxxxx>
> ---
> drivers/clk/qcom/common.c | 13 ++++++++++---
> 1 file changed, 10 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/clk/qcom/common.c b/drivers/clk/qcom/common.c
> index c112eba..3541a9a 100644
> --- a/drivers/clk/qcom/common.c
> +++ b/drivers/clk/qcom/common.c
> @@ -213,7 +213,10 @@ int qcom_cc_really_probe(struct platform_device *pdev,
> if (ret)
> return ret;
>
> - devm_add_action(dev, qcom_cc_del_clk_provider, pdev->dev.of_node);
> + ret = devm_add_action(dev, qcom_cc_del_clk_provider,
> + pdev->dev.of_node);
> + if (ret)
> + return ret;

So now we don't remove the clk provider on allocation failure?
Confused.

>
> reset = &cc->reset;
> reset->rcdev.of_node = dev->of_node;
> @@ -236,8 +239,12 @@ int qcom_cc_really_probe(struct platform_device *pdev,
> return ret;
> }
>
> - devm_add_action(dev, qcom_cc_gdsc_unregister, dev);
> -
> + ret = devm_add_action(dev, qcom_cc_gdsc_unregister, dev);
> + if (ret) {
> + if (desc->gdscs && desc->num_gdscs)
> + gdsc_unregister(dev);
> + return ret;
> + }
>
> return 0;
> }

You seem to have missed the reset devm action. Why?

Also, I wonder if we could have devm_add_action() or some other
new devm_add_action() wrapper that tried to add the action, and
if it failed it ran the action right there and returned the
-ENOMEM? So then we can just have:

ret = devm_add_action_or_do_it(dev, qcom_cc_gdsc_unregister, dev)
if (ret)
return ret;

and we're assured that on the failure path we'll have already
called qcom_cc_gdsc_unregister.

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