Re: [PATCH v4 3/4] powercap/drivers/dtpm: Add API for dynamic thermal power management

[Lukasz Luba]

Hi Daniel,

I realized small issue when I went through this new mutex code
(which is safer IMHO).

On 12/1/20 7:28 PM, Daniel Lezcano wrote:

[snip]

> +int dtpm_register(const char *name, struct dtpm *dtpm, struct dtpm *parent)
> +{
> +	struct powercap_zone *pcz;
> +
> +	if (!pct)
> +		return -EAGAIN;
> +
> +	if (root && !parent)
> +		return -EBUSY;
> +
> +	if (!root && parent)
> +		return -EINVAL;
> +
> +	if (parent && parent->ops)
> +		return -EINVAL;
> +

Maybe it worth to add a check of dtpm pointer here, just to play safe?

	if (!dtpm)
		return -EINVAL;

The dtpm->ops might explode when we don't capture this miss-usage during
reviews of future drivers/shim layers. What do you think?


> +	if (dtpm->ops && !(dtpm->ops->set_power_uw &&
> +			   dtpm->ops->get_power_uw &&
> +			   dtpm->ops->release))
> +		return -EINVAL;
> +

I am going to stress test the whole series with hotplug today
and add review for patch 4/4.

Regards,
Lukasz