[PATCH v6 05/12] platform/x86: alienware-wmi-wmax: Improve platform profile probe

Kurt Borja posted 12 patches 9 months, 1 week ago
There is a newer version of this series
[PATCH v6 05/12] platform/x86: alienware-wmi-wmax: Improve platform profile probe
Posted by Kurt Borja 9 months, 1 week ago
Get and store the AWCC system description in alienware_awcc_setup()
instead of awcc_platform_profile_probe() and add a check for integer
overflows to avoid misbehaviors.

While at it, replace set_bit() with it's non-atomic version __set_bit()
because `choices` belong to this thread only.

Reviewed-by: Armin Wolf <W_Armin@gmx.de>
Signed-off-by: Kurt Borja <kuurtb@gmail.com>
---
 drivers/platform/x86/dell/alienware-wmi-wmax.c | 61 +++++++++++++++++++-------
 1 file changed, 46 insertions(+), 15 deletions(-)

diff --git a/drivers/platform/x86/dell/alienware-wmi-wmax.c b/drivers/platform/x86/dell/alienware-wmi-wmax.c
index a8a13779793abbcc8d1263474cac6227d524a6f5..0530f25b956f73f47c0354f40dac2910448c894e 100644
--- a/drivers/platform/x86/dell/alienware-wmi-wmax.c
+++ b/drivers/platform/x86/dell/alienware-wmi-wmax.c
@@ -38,6 +38,9 @@
 /* Some IDs have a BIT(8) flag that we ignore */
 #define AWCC_RESOURCE_ID_MASK			GENMASK(7, 0)
 
+/* Arbitrary limit based on supported models */
+#define AWCC_MAX_RES_COUNT			16
+
 static bool force_platform_profile;
 module_param_unsafe(force_platform_profile, bool, 0);
 MODULE_PARM_DESC(force_platform_profile, "Forces auto-detecting thermal profiles without checking if WMI thermal backend is available");
@@ -212,6 +215,17 @@ struct wmax_u32_args {
 
 struct awcc_priv {
 	struct wmi_device *wdev;
+	union {
+		u32 system_description;
+		struct {
+			u8 fan_count;
+			u8 temp_count;
+			u8 unknown_count;
+			u8 profile_count;
+		};
+		u8 res_count[4];
+	};
+
 	struct device *ppdev;
 	u8 supported_profiles[PLATFORM_PROFILE_LAST];
 };
@@ -624,37 +638,40 @@ static int awcc_platform_profile_probe(void *drvdata, unsigned long *choices)
 	enum platform_profile_option profile;
 	struct awcc_priv *priv = drvdata;
 	enum awcc_thermal_profile mode;
-	u8 sys_desc[4];
-	u32 first_mode;
+	u8 id, offset = 0;
 	u32 out_data;
 	int ret;
-	u8 id;
 
-	ret = awcc_thermal_information(priv->wdev, AWCC_OP_GET_SYSTEM_DESCRIPTION,
-				       0, (u32 *) &sys_desc);
-	if (ret < 0)
-		return ret;
-
-	first_mode = sys_desc[0] + sys_desc[1];
-
-	for (u32 i = 0; i < sys_desc[3]; i++) {
-		ret = awcc_op_get_resource_id(priv->wdev, i + first_mode, &out_data);
+	/*
+	 * Thermal profile IDs are listed last at offset
+	 *	fan_count + temp_count + unknown_count
+	 */
+	for (unsigned int i = 0; i < ARRAY_SIZE(priv->res_count) - 1; i++)
+		offset += priv->res_count[i];
 
+	for (unsigned int i = 0; i < priv->profile_count; i++) {
+		ret = awcc_op_get_resource_id(priv->wdev, i + offset, &out_data);
 		if (ret == -EIO)
 			return ret;
 
+		/*
+		 * Some devices report an incorrect number of thermal profiles
+		 * so the resource ID list may end prematurely
+		 */
 		if (ret == -EBADRQC)
 			break;
 
 		id = FIELD_GET(AWCC_RESOURCE_ID_MASK, out_data);
-		if (!is_awcc_thermal_profile_id(id))
+		if (!is_awcc_thermal_profile_id(id)) {
+			dev_dbg(&priv->wdev->dev, "Unmapped thermal profile ID 0x%02x\n", id);
 			continue;
+		}
 
 		mode = FIELD_GET(AWCC_THERMAL_MODE_MASK, id);
 		profile = awcc_mode_to_platform_profile[mode];
 		priv->supported_profiles[profile] = id;
 
-		set_bit(profile, choices);
+		__set_bit(profile, choices);
 	}
 
 	if (bitmap_empty(choices, PLATFORM_PROFILE_LAST))
@@ -664,7 +681,7 @@ static int awcc_platform_profile_probe(void *drvdata, unsigned long *choices)
 		priv->supported_profiles[PLATFORM_PROFILE_PERFORMANCE] =
 			AWCC_THERMAL_MODE_GMODE;
 
-		set_bit(PLATFORM_PROFILE_PERFORMANCE, choices);
+		__set_bit(PLATFORM_PROFILE_PERFORMANCE, choices);
 	}
 
 	return 0;
@@ -695,6 +712,20 @@ static int alienware_awcc_setup(struct wmi_device *wdev)
 	if (!priv)
 		return -ENOMEM;
 
+	ret = awcc_thermal_information(wdev, AWCC_OP_GET_SYSTEM_DESCRIPTION,
+				       0, &priv->system_description);
+	if (ret < 0)
+		return ret;
+
+	/* Sanity check */
+	for (unsigned int i = 0; i < ARRAY_SIZE(priv->res_count); i++) {
+		if (priv->res_count[i] > AWCC_MAX_RES_COUNT) {
+			dev_err(&wdev->dev, "Malformed system description: 0x%08x\n",
+				priv->system_description);
+			return -ENXIO;
+		}
+	}
+
 	priv->wdev = wdev;
 	dev_set_drvdata(&wdev->dev, priv);
 

-- 
2.48.1
Re: [PATCH v6 05/12] platform/x86: alienware-wmi-wmax: Improve platform profile probe
Posted by Ilpo Järvinen 8 months, 3 weeks ago
On Thu, 13 Mar 2025, Kurt Borja wrote:

> Get and store the AWCC system description in alienware_awcc_setup()
> instead of awcc_platform_profile_probe() and add a check for integer
> overflows to avoid misbehaviors.
> 
> While at it, replace set_bit() with it's non-atomic version __set_bit()
> because `choices` belong to this thread only.
> 
> Reviewed-by: Armin Wolf <W_Armin@gmx.de>
> Signed-off-by: Kurt Borja <kuurtb@gmail.com>
> ---
>  drivers/platform/x86/dell/alienware-wmi-wmax.c | 61 +++++++++++++++++++-------
>  1 file changed, 46 insertions(+), 15 deletions(-)
> 
> diff --git a/drivers/platform/x86/dell/alienware-wmi-wmax.c b/drivers/platform/x86/dell/alienware-wmi-wmax.c
> index a8a13779793abbcc8d1263474cac6227d524a6f5..0530f25b956f73f47c0354f40dac2910448c894e 100644
> --- a/drivers/platform/x86/dell/alienware-wmi-wmax.c
> +++ b/drivers/platform/x86/dell/alienware-wmi-wmax.c
> @@ -38,6 +38,9 @@
>  /* Some IDs have a BIT(8) flag that we ignore */
>  #define AWCC_RESOURCE_ID_MASK			GENMASK(7, 0)
>  
> +/* Arbitrary limit based on supported models */
> +#define AWCC_MAX_RES_COUNT			16
> +
>  static bool force_platform_profile;
>  module_param_unsafe(force_platform_profile, bool, 0);
>  MODULE_PARM_DESC(force_platform_profile, "Forces auto-detecting thermal profiles without checking if WMI thermal backend is available");
> @@ -212,6 +215,17 @@ struct wmax_u32_args {
>  
>  struct awcc_priv {
>  	struct wmi_device *wdev;
> +	union {
> +		u32 system_description;
> +		struct {
> +			u8 fan_count;
> +			u8 temp_count;
> +			u8 unknown_count;
> +			u8 profile_count;
> +		};
> +		u8 res_count[4];
> +	};
> +
>  	struct device *ppdev;
>  	u8 supported_profiles[PLATFORM_PROFILE_LAST];
>  };
> @@ -624,37 +638,40 @@ static int awcc_platform_profile_probe(void *drvdata, unsigned long *choices)
>  	enum platform_profile_option profile;
>  	struct awcc_priv *priv = drvdata;
>  	enum awcc_thermal_profile mode;
> -	u8 sys_desc[4];
> -	u32 first_mode;
> +	u8 id, offset = 0;
>  	u32 out_data;
>  	int ret;
> -	u8 id;
>  
> -	ret = awcc_thermal_information(priv->wdev, AWCC_OP_GET_SYSTEM_DESCRIPTION,
> -				       0, (u32 *) &sys_desc);
> -	if (ret < 0)
> -		return ret;
> -
> -	first_mode = sys_desc[0] + sys_desc[1];
> -
> -	for (u32 i = 0; i < sys_desc[3]; i++) {
> -		ret = awcc_op_get_resource_id(priv->wdev, i + first_mode, &out_data);
> +	/*
> +	 * Thermal profile IDs are listed last at offset
> +	 *	fan_count + temp_count + unknown_count
> +	 */
> +	for (unsigned int i = 0; i < ARRAY_SIZE(priv->res_count) - 1; i++)
> +		offset += priv->res_count[i];

Doesn't this change go slightly beyond what its changelog describes, could 
you please amend the changelog to explain it.
>  
> +	for (unsigned int i = 0; i < priv->profile_count; i++) {
> +		ret = awcc_op_get_resource_id(priv->wdev, i + offset, &out_data);
>  		if (ret == -EIO)
>  			return ret;
>  
> +		/*
> +		 * Some devices report an incorrect number of thermal profiles
> +		 * so the resource ID list may end prematurely
> +		 */
>  		if (ret == -EBADRQC)
>  			break;
>  
>  		id = FIELD_GET(AWCC_RESOURCE_ID_MASK, out_data);
> -		if (!is_awcc_thermal_profile_id(id))
> +		if (!is_awcc_thermal_profile_id(id)) {
> +			dev_dbg(&priv->wdev->dev, "Unmapped thermal profile ID 0x%02x\n", id);
>  			continue;
> +		}
>  
>  		mode = FIELD_GET(AWCC_THERMAL_MODE_MASK, id);
>  		profile = awcc_mode_to_platform_profile[mode];
>  		priv->supported_profiles[profile] = id;
>  
> -		set_bit(profile, choices);
> +		__set_bit(profile, choices);
>  	}
>  
>  	if (bitmap_empty(choices, PLATFORM_PROFILE_LAST))
> @@ -664,7 +681,7 @@ static int awcc_platform_profile_probe(void *drvdata, unsigned long *choices)
>  		priv->supported_profiles[PLATFORM_PROFILE_PERFORMANCE] =
>  			AWCC_THERMAL_MODE_GMODE;
>  
> -		set_bit(PLATFORM_PROFILE_PERFORMANCE, choices);
> +		__set_bit(PLATFORM_PROFILE_PERFORMANCE, choices);
>  	}
>  
>  	return 0;
> @@ -695,6 +712,20 @@ static int alienware_awcc_setup(struct wmi_device *wdev)
>  	if (!priv)
>  		return -ENOMEM;
>  
> +	ret = awcc_thermal_information(wdev, AWCC_OP_GET_SYSTEM_DESCRIPTION,
> +				       0, &priv->system_description);
> +	if (ret < 0)
> +		return ret;
> +
> +	/* Sanity check */
> +	for (unsigned int i = 0; i < ARRAY_SIZE(priv->res_count); i++) {
> +		if (priv->res_count[i] > AWCC_MAX_RES_COUNT) {
> +			dev_err(&wdev->dev, "Malformed system description: 0x%08x\n",
> +				priv->system_description);
> +			return -ENXIO;
> +		}
> +	}
> +
>  	priv->wdev = wdev;
>  	dev_set_drvdata(&wdev->dev, priv);
>  
> 
> 

-- 
 i.
Re: [PATCH v6 05/12] platform/x86: alienware-wmi-wmax: Improve platform profile probe
Posted by Kurt Borja 8 months, 3 weeks ago
On Fri Mar 28, 2025 at 12:03 PM -03, Ilpo Järvinen wrote:
> On Thu, 13 Mar 2025, Kurt Borja wrote:
>
>> Get and store the AWCC system description in alienware_awcc_setup()
>> instead of awcc_platform_profile_probe() and add a check for integer
>> overflows to avoid misbehaviors.
>> 
>> While at it, replace set_bit() with it's non-atomic version __set_bit()
>> because `choices` belong to this thread only.
>> 
>> Reviewed-by: Armin Wolf <W_Armin@gmx.de>
>> Signed-off-by: Kurt Borja <kuurtb@gmail.com>
>> ---
>>  drivers/platform/x86/dell/alienware-wmi-wmax.c | 61 +++++++++++++++++++-------
>>  1 file changed, 46 insertions(+), 15 deletions(-)
>> 
>> diff --git a/drivers/platform/x86/dell/alienware-wmi-wmax.c b/drivers/platform/x86/dell/alienware-wmi-wmax.c
>> index a8a13779793abbcc8d1263474cac6227d524a6f5..0530f25b956f73f47c0354f40dac2910448c894e 100644
>> --- a/drivers/platform/x86/dell/alienware-wmi-wmax.c
>> +++ b/drivers/platform/x86/dell/alienware-wmi-wmax.c
>> @@ -38,6 +38,9 @@
>>  /* Some IDs have a BIT(8) flag that we ignore */
>>  #define AWCC_RESOURCE_ID_MASK			GENMASK(7, 0)
>>  
>> +/* Arbitrary limit based on supported models */
>> +#define AWCC_MAX_RES_COUNT			16
>> +
>>  static bool force_platform_profile;
>>  module_param_unsafe(force_platform_profile, bool, 0);
>>  MODULE_PARM_DESC(force_platform_profile, "Forces auto-detecting thermal profiles without checking if WMI thermal backend is available");
>> @@ -212,6 +215,17 @@ struct wmax_u32_args {
>>  
>>  struct awcc_priv {
>>  	struct wmi_device *wdev;
>> +	union {
>> +		u32 system_description;
>> +		struct {
>> +			u8 fan_count;
>> +			u8 temp_count;
>> +			u8 unknown_count;
>> +			u8 profile_count;
>> +		};
>> +		u8 res_count[4];
>> +	};
>> +
>>  	struct device *ppdev;
>>  	u8 supported_profiles[PLATFORM_PROFILE_LAST];
>>  };
>> @@ -624,37 +638,40 @@ static int awcc_platform_profile_probe(void *drvdata, unsigned long *choices)
>>  	enum platform_profile_option profile;
>>  	struct awcc_priv *priv = drvdata;
>>  	enum awcc_thermal_profile mode;
>> -	u8 sys_desc[4];
>> -	u32 first_mode;
>> +	u8 id, offset = 0;
>>  	u32 out_data;
>>  	int ret;
>> -	u8 id;
>>  
>> -	ret = awcc_thermal_information(priv->wdev, AWCC_OP_GET_SYSTEM_DESCRIPTION,
>> -				       0, (u32 *) &sys_desc);
>> -	if (ret < 0)
>> -		return ret;
>> -
>> -	first_mode = sys_desc[0] + sys_desc[1];
>> -
>> -	for (u32 i = 0; i < sys_desc[3]; i++) {
>> -		ret = awcc_op_get_resource_id(priv->wdev, i + first_mode, &out_data);
>> +	/*
>> +	 * Thermal profile IDs are listed last at offset
>> +	 *	fan_count + temp_count + unknown_count
>> +	 */
>> +	for (unsigned int i = 0; i < ARRAY_SIZE(priv->res_count) - 1; i++)
>> +		offset += priv->res_count[i];
>
> Doesn't this change go slightly beyond what its changelog describes, could 
> you please amend the changelog to explain it.

Sure! Only difference would be that now we also sum the unknown_ids.
I'll mention it.

>>  
>> +	for (unsigned int i = 0; i < priv->profile_count; i++) {
>> +		ret = awcc_op_get_resource_id(priv->wdev, i + offset, &out_data);
>>  		if (ret == -EIO)
>>  			return ret;
>>  
>> +		/*
>> +		 * Some devices report an incorrect number of thermal profiles
>> +		 * so the resource ID list may end prematurely
>> +		 */
>>  		if (ret == -EBADRQC)
>>  			break;
>>  
>>  		id = FIELD_GET(AWCC_RESOURCE_ID_MASK, out_data);
>> -		if (!is_awcc_thermal_profile_id(id))
>> +		if (!is_awcc_thermal_profile_id(id)) {
>> +			dev_dbg(&priv->wdev->dev, "Unmapped thermal profile ID 0x%02x\n", id);
>>  			continue;
>> +		}
>>  
>>  		mode = FIELD_GET(AWCC_THERMAL_MODE_MASK, id);
>>  		profile = awcc_mode_to_platform_profile[mode];
>>  		priv->supported_profiles[profile] = id;
>>  
>> -		set_bit(profile, choices);
>> +		__set_bit(profile, choices);
>>  	}
>>  
>>  	if (bitmap_empty(choices, PLATFORM_PROFILE_LAST))
>> @@ -664,7 +681,7 @@ static int awcc_platform_profile_probe(void *drvdata, unsigned long *choices)
>>  		priv->supported_profiles[PLATFORM_PROFILE_PERFORMANCE] =
>>  			AWCC_THERMAL_MODE_GMODE;
>>  
>> -		set_bit(PLATFORM_PROFILE_PERFORMANCE, choices);
>> +		__set_bit(PLATFORM_PROFILE_PERFORMANCE, choices);
>>  	}
>>  
>>  	return 0;
>> @@ -695,6 +712,20 @@ static int alienware_awcc_setup(struct wmi_device *wdev)
>>  	if (!priv)
>>  		return -ENOMEM;
>>  
>> +	ret = awcc_thermal_information(wdev, AWCC_OP_GET_SYSTEM_DESCRIPTION,
>> +				       0, &priv->system_description);
>> +	if (ret < 0)
>> +		return ret;
>> +
>> +	/* Sanity check */
>> +	for (unsigned int i = 0; i < ARRAY_SIZE(priv->res_count); i++) {
>> +		if (priv->res_count[i] > AWCC_MAX_RES_COUNT) {
>> +			dev_err(&wdev->dev, "Malformed system description: 0x%08x\n",
>> +				priv->system_description);
>> +			return -ENXIO;
>> +		}
>> +	}
>> +
>>  	priv->wdev = wdev;
>>  	dev_set_drvdata(&wdev->dev, priv);
>>  
>> 
>>