Re: [PATCH v25 02/10] power: reset: reboot-mode: Add support for predefined reboot modes

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] Predefined modes overlapping with DT-defined modes cause duplicate entries in the sysfs `reboot_modes` attribute.
--

commit 394fababa44a1d093815c91cc11774a6de1c1f6b
Author: Shivendra Pratap <shivendra.pratap@oss.qualcomm.com>

power: reset: reboot-mode: Add support for predefined reboot modes
    
Extend the reboot-mode framework to support driver-defined predefined reboot
modes. Add a centralized initcall to initialize driver state along with
predefined modes.

> diff --git a/drivers/power/reset/reboot-mode.c b/drivers/power/reset/reboot-mode.c
> index 328fa37598df3..fd61de2263836 100644
> --- a/drivers/power/reset/reboot-mode.c
> +++ b/drivers/power/reset/reboot-mode.c

[ ... ]

> @@ -160,11 +234,38 @@ static int reboot_mode_create_device(struct reboot_mode_driver *reboot)
>  	return 0;
>  
>  error:
> -	reboot_mode_release_list(priv);
> +	reboot_mode_release_list(&priv->head);
>  	kfree(priv);
>  	return ret;
>  }
>  
> +static int reboot_mode_add_predefined_modes(struct reboot_mode_driver *reboot)
> +{
> +	const struct reboot_mode_entry *modes = reboot->predefined_modes;
> +	struct mode_info *info;
> +	size_t i;
> +
> +	if (!modes)
> +		return 0;
> +
> +	for (i = 0; i < reboot->predefined_mode_count; i++) {
> +		if (modes[i].name && strpbrk(modes[i].name, "\n ,/"))
> +			return -EINVAL;
> +
> +		if (!modes[i].count || modes[i].count > ARRAY_SIZE(modes[i].magic))
> +			return -EINVAL;
> +
> +		info = reboot_mode_create_info(reboot->dev, modes[i].name,
> +					       modes[i].magic, modes[i].count);
> +		if (IS_ERR(info))
> +			return PTR_ERR(info);
> +
> +		list_add_tail(&info->list, &reboot->head);

[Severity: Medium]
Will this lead to duplicate string entries in the sysfs reboot_modes
attribute?

If a reboot mode provided by the Device Tree has the same name as one of the
driver's predefined modes, reboot_mode_register() parses the DT property and
adds it to the reboot->head list first.

Immediately after, reboot_mode_add_predefined_modes() blindly appends the
predefined mode to the same list here without checking if an entry with that
name already exists.

The duplicate entries are unconditionally propagated to the sysfs structure in
reboot_mode_create_device(). This will cause reboot_modes_show() to print
all modes sequentially, resulting in duplicate strings in sysfs when userspace
reads the /sys/class/reboot-mode/.../reboot_modes file.

> +	}
> +
> +	return 0;
> +}
> +
>  /**
>   * reboot_mode_register - register a reboot mode driver
>   * @reboot: reboot mode driver

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260914-arm-psci-system_reset2-vendor-reboots-v25-0-4aaf5c09b5c2@oss.qualcomm.com?part=2