linux-kernel - Re: [PATCH net-next v6 04/12] net: pse-pd: Add support for PSE power domains

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <Z9fyZkAOB602cFJY@pengutronix.de>
Date: Mon, 17 Mar 2025 10:59:02 +0100
From: Oleksij Rempel <o.rempel@...gutronix.de>
To: Kory Maincent <kory.maincent@...tlin.com>
Cc: Andrew Lunn <andrew@...n.ch>, "David S. Miller" <davem@...emloft.net>,
	Eric Dumazet <edumazet@...gle.com>,
	Jakub Kicinski <kuba@...nel.org>, Paolo Abeni <pabeni@...hat.com>,
	Jonathan Corbet <corbet@....net>,
	Donald Hunter <donald.hunter@...il.com>,
	Rob Herring <robh@...nel.org>, Andrew Lunn <andrew+netdev@...n.ch>,
	Simon Horman <horms@...nel.org>,
	Heiner Kallweit <hkallweit1@...il.com>,
	Russell King <linux@...linux.org.uk>,
	Krzysztof Kozlowski <krzk+dt@...nel.org>,
	Conor Dooley <conor+dt@...nel.org>,
	Liam Girdwood <lgirdwood@...il.com>,
	Mark Brown <broonie@...nel.org>,
	Thomas Petazzoni <thomas.petazzoni@...tlin.com>,
	netdev@...r.kernel.org, linux-doc@...r.kernel.org,
	Kyle Swenson <kyle.swenson@....tech>,
	Dent Project <dentproject@...uxfoundation.org>,
	kernel@...gutronix.de,
	Maxime Chevallier <maxime.chevallier@...tlin.com>,
	devicetree@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH net-next v6 04/12] net: pse-pd: Add support for PSE power
 domains

On Tue, Mar 04, 2025 at 11:18:53AM +0100, Kory Maincent wrote:
> +/**
> + * pse_flush_pw_ds - flush all PSE power domains of a PSE
> + * @pcdev: a pointer to the initialized PSE controller device
> + */
> +static void pse_flush_pw_ds(struct pse_controller_dev *pcdev)
> +{
> +	struct pse_power_domain *pw_d;
> +	int i;
> +
> +	for (i = 0; i < pcdev->nr_lines; i++) {
> +		if (!pcdev->pi[i].pw_d)
> +			continue;
> +
> +		pw_d = xa_load(&pse_pw_d_map, pcdev->pi[i].pw_d->id);
> +		if (pw_d) {
> +			regulator_put(pw_d->supply);
> +			xa_erase(&pse_pw_d_map, pw_d->id);
> +		}
> +	}
> +}
> +
> +/**
> + * devm_pse_alloc_pw_d - allocate a new PSE power domain for a device
> + * @dev: device that is registering this PSE power domain
> + *
> + * Return: Pointer to the newly allocated PSE power domain or error pointers
> + */
> +static struct pse_power_domain *devm_pse_alloc_pw_d(struct device *dev)
> +{
> +	struct pse_power_domain *pw_d;
> +	int index, ret;
> +
> +	pw_d = devm_kzalloc(dev, sizeof(*pw_d), GFP_KERNEL);
> +	if (!pw_d)
> +		return ERR_PTR(-ENOMEM);
> +
> +	ret = xa_alloc(&pse_pw_d_map, &index, pw_d, XA_LIMIT(1, INT_MAX), GFP_KERNEL);

#define PSE_PW_D_LIMIT INT_MAX

XA_LIMIT(1, PSE_PW_D_LIMIT)

> +	if (ret)
> +		return ERR_PTR(ret);
> +
> +	pw_d->id = index;
> +	return pw_d;
> +}
> +
> +/**
> + * pse_register_pw_ds - register the PSE power domains for a PSE
> + * @pcdev: a pointer to the PSE controller device
> + *
> + * Return: 0 on success and failure value on error
> + */
> +static int pse_register_pw_ds(struct pse_controller_dev *pcdev)
> +{
> +	int i;
> +
> +	for (i = 0; i < pcdev->nr_lines; i++) {
> +		struct regulator_dev *rdev = pcdev->pi[i].rdev;
> +		struct pse_power_domain *pw_d;
> +		struct regulator *supply;
> +		bool present = false;
> +		unsigned long index;
> +
> +		/* No regulator or regulator parent supply registered.
> +		 * We need a regulator parent to register a PSE power domain
> +		 */
> +		if (!rdev || !rdev->supply)
> +			continue;
> +

Should we use xa_lock() before iteration over the map?

> +		xa_for_each(&pse_pw_d_map, index, pw_d) {
> +			/* Power supply already registered as a PSE power
> +			 * domain.
> +			 */
> +			if (regulator_is_equal(pw_d->supply, rdev->supply)) {
> +				present = true;
> +				pcdev->pi[i].pw_d = pw_d;
> +				break;
> +			}
> +		}
> +		if (present)
> +			continue;
> +
> +		pw_d = devm_pse_alloc_pw_d(pcdev->dev);
> +		if (IS_ERR_OR_NULL(pw_d))
> +			return PTR_ERR(pw_d);

It is better to break the loop and roll back previous allocations.

> +
> +		supply = regulator_get(&rdev->dev, rdev->supply_name);
> +		if (IS_ERR(supply)) {
> +			xa_erase(&pse_pw_d_map, pw_d->id);
> +			return PTR_ERR(supply);

same here.

> +		}
> +
> +		pw_d->supply = supply;
> +		pcdev->pi[i].pw_d = pw_d;
> +	}
> +
> +	return 0;
> +}
-- 
Pengutronix e.K.                           |                             |
Steuerwalder Str. 21                       | http://www.pengutronix.de/  |
31137 Hildesheim, Germany                  | Phone: +49-5121-206917-0    |
Amtsgericht Hildesheim, HRA 2686           | Fax:   +49-5121-206917-5555 |