Re: [PATCH v3 2/2] platform/x86: thinklmi: improved DMI handling

[Ilpo Järvinen]

On Mon, 9 Jun 2025, Mark Pearson wrote:

> Fix issues reported by kernel test robot.
>  - Require DMI for think-lmi.
>  - Check return from getting serial string
> 
> Reported-by: kernel test robot <lkp@xxxxxxxxx>
> Closes: https://lore.kernel.org/oe-kbuild-all/202506062319.F0IpDxF6-lkp@xxxxxxxxx/
> 
> Signed-off-by: Mark Pearson <mpearson-lenovo@xxxxxxxxx>
> ---
>  - New patch added to series.
> 
>  drivers/platform/x86/lenovo/Kconfig     | 1 +
>  drivers/platform/x86/lenovo/think-lmi.c | 8 +++++---
>  2 files changed, 6 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/platform/x86/lenovo/Kconfig b/drivers/platform/x86/lenovo/Kconfig
> index a4b565283768..207dd7f88ed0 100644
> --- a/drivers/platform/x86/lenovo/Kconfig
> +++ b/drivers/platform/x86/lenovo/Kconfig
> @@ -197,6 +197,7 @@ config THINKPAD_ACPI_HOTKEY_POLL
>  config THINKPAD_LMI
>  	tristate "Lenovo WMI-based systems management driver"
>  	depends on ACPI_WMI
> +	depends on DMI
>  	select FW_ATTR_CLASS
>  	help
>  	  This driver allows changing BIOS settings on Lenovo machines whose
> diff --git a/drivers/platform/x86/lenovo/think-lmi.c b/drivers/platform/x86/lenovo/think-lmi.c
> index 143d9fdedb65..8f70c60f791f 100644
> --- a/drivers/platform/x86/lenovo/think-lmi.c
> +++ b/drivers/platform/x86/lenovo/think-lmi.c
> @@ -772,6 +772,7 @@ static ssize_t certificate_store(struct kobject *kobj,
>  	struct tlmi_pwd_setting *setting = to_tlmi_pwd_setting(kobj);
>  	enum cert_install_mode install_mode = TLMI_CERT_INSTALL;
>  	char *auth_str, *new_cert;
> +	const char *serial;
>  	char *signature;
>  	char *guid;
>  	int ret;
> @@ -789,9 +790,10 @@ static ssize_t certificate_store(struct kobject *kobj,
>  			return -EACCES;
>  
>  		/* Format: 'serial#, signature' */
> -		auth_str = cert_command(setting,
> -					dmi_get_system_info(DMI_PRODUCT_SERIAL),
> -					setting->signature);
> +		serial = dmi_get_system_info(DMI_PRODUCT_SERIAL);
> +		if (!serial)
> +			return -EINVAL;

This should not return -EINVAL as it is not a problem with the input 
parameters. Perhaps -ENODEV would make sense instead?

> +		auth_str = cert_command(setting, serial, setting->signature);
>  		if (!auth_str)
>  			return -ENOMEM;
>  
> 

-- 
 i.