Re: [PATCH v7 3/4] firmware: arm_scmi: Add SCMI v3.2 pincontrol protocol basic support

[Andy Shevchenko]

On Tue, Apr 02, 2024 at 10:22:23AM +0800, Peng Fan (OSS) wrote:

..

> +#include <linux/module.h>
> +#include <linux/scmi_protocol.h>
> +#include <linux/slab.h>

Please, follow IWYU principle, a lot of headers are missed.

> +#include "common.h"
> +#include "protocols.h"

..

> +		ret = scmi_pinctrl_get_pin_info(ph, selector,
> +						&pi->pins[selector]);

It's netter as a single line.

> +		if (ret)
> +			return ret;
> +	}

..

> +static int scmi_pinctrl_protocol_init(const struct scmi_protocol_handle *ph)
> +{
> +	int ret;
> +	u32 version;
> +	struct scmi_pinctrl_info *pinfo;
> +
> +	ret = ph->xops->version_get(ph, &version);
> +	if (ret)
> +		return ret;
> +
> +	dev_dbg(ph->dev, "Pinctrl Version %d.%d\n",
> +		PROTOCOL_REV_MAJOR(version), PROTOCOL_REV_MINOR(version));
> +
> +	pinfo = devm_kzalloc(ph->dev, sizeof(*pinfo), GFP_KERNEL);
> +	if (!pinfo)
> +		return -ENOMEM;
> +
> +	ret = scmi_pinctrl_attributes_get(ph, pinfo);
> +	if (ret)
> +		return ret;
> +
> +	pinfo->pins = devm_kcalloc(ph->dev, pinfo->nr_pins,
> +				   sizeof(*pinfo->pins), GFP_KERNEL);
> +	if (!pinfo->pins)
> +		return -ENOMEM;
> +
> +	pinfo->groups = devm_kcalloc(ph->dev, pinfo->nr_groups,
> +				     sizeof(*pinfo->groups), GFP_KERNEL);
> +	if (!pinfo->groups)
> +		return -ENOMEM;
> +
> +	pinfo->functions = devm_kcalloc(ph->dev, pinfo->nr_functions,
> +					sizeof(*pinfo->functions), GFP_KERNEL);
> +	if (!pinfo->functions)
> +		return -ENOMEM;
> +
> +	pinfo->version = version;
> +
> +	return ph->set_priv(ph, pinfo, version);

Same comments as per previous version. devm_ here is simply wrong.
It breaks the order of freeing resources.

I.o.w. I see *no guarantee* that these init-deinit functions will be properly
called from the respective probe-remove. Moreover the latter one may also have
its own devm allocations (which are rightfully placed) and you get completely
out of control the resource management.

> +}

-- 
With Best Regards,
Andy Shevchenko