Re: [PATCH v3 3/4] leds: menf21bmc: Convert to dev_err_probe()

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:

Pre-existing issues:
- [High] The `menf21bmc_led_set` function sleeps but is incorrectly assigned to the non-blocking `brightness_set` callback.
--

--- Patch [3]: [PATCH v3 3/4] leds: menf21bmc: Convert to dev_err_probe() ---
commit 47baf6269572a611e45209e561552d7a4bd3af39
Author: Arunachalam <arun07172003@gmail.com>

leds: menf21bmc: Convert to dev_err_probe()
    
Replace open-coded dev_err() + return pattern with dev_err_probe(),
which also handles -EPROBE_DEFER correctly.

> diff --git a/drivers/leds/leds-menf21bmc.c b/drivers/leds/leds-menf21bmc.c
> index 6b1b471606026..a7e4db4879d81 100644
> --- a/drivers/leds/leds-menf21bmc.c
> +++ b/drivers/leds/leds-menf21bmc.c
> @@ -84,10 +84,8 @@ static int menf21bmc_led_probe(struct platform_device *pdev)
>  		leds[i].cdev.brightness_set = menf21bmc_led_set;

[Severity: High]
This is a pre-existing issue, but does assigning this to brightness_set instead
of brightness_set_blocking risk a scheduling while atomic bug?

The menf21bmc_led_set() function acquires a mutex and calls sleeping I2C
functions:

drivers/leds/leds-menf21bmc.c:menf21bmc_led_set() {
    ...
	mutex_lock(&led_lock);
	led_val = i2c_smbus_read_byte_data(led->i2c_client,
					   BMC_CMD_LED_GET_SET);
    ...
}

If an atomic-context trigger like 'timer' or 'heartbeat' is selected for this
LED via sysfs, the LED core could call this non-blocking hook from an atomic
context, which can crash the system.

>  		leds[i].i2c_client = i2c_client;
>  		ret = devm_led_classdev_register(&pdev->dev, &leds[i].cdev);
> -		if (ret < 0) {
> -			dev_err(&pdev->dev, "failed to register LED device\n");
> -			return ret;
> -		}
> +		if (ret < 0)
> +			return dev_err_probe(&pdev->dev, ret, "failed to register LED device\n");
>  	}
>  	dev_info(&pdev->dev, "MEN 140F21P00 BMC LED device enabled\n");
>

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260725081349.8556-1-arun07172003@gmail.com?part=3