Re: [PATCH v2 3/5] drm/xe/hwmon: Correct group selection for memory controller temperature

["Poosa, Karthik" <karthik.poosa@intel.com>]

On 02-09-2026 23:47, sashiko-bot@kernel.org wrote:
> Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
>
> Pre-existing issues:
> - [High] Unaligned memory access due to misaligned pointer cast.
> --
>
> commit bce6aebc01fe7736c7ce377f855345b461ab89e3
> Author: Karthik Poosa <karthik.poosa@intel.com>
>
> drm/xe/hwmon: Correct group selection for memory controller temperature
>      
> Read all the necessary groups when reading memory controller
> temperature in get_mc_temp().
>
>> diff --git a/drivers/gpu/drm/xe/xe_hwmon.c b/drivers/gpu/drm/xe/xe_hwmon.c
>> index 51a6664eec485..3a675d7b6758b 100644
>> --- a/drivers/gpu/drm/xe/xe_hwmon.c
>> +++ b/drivers/gpu/drm/xe/xe_hwmon.c
> [ ... ]
>> @@ -883,7 +883,7 @@ static int get_mc_temp(struct xe_hwmon *hwmon, long *val)
>>   	int ret, i, count = 0;
>>   	s32 average = 0;
>>   
>> -	for (i = 0; i < DIV_ROUND_UP(TEMP_LIMIT_MAX, sizeof(u32)); i++) {
>> +	for (i = 0; i < DIV_ROUND_UP(hwmon->temp.count, sizeof(u32)); i++) {
>>   		ret = xe_pcode_read(root_tile, PCODE_MBOX(PCODE_THERMAL_INFO, READ_THERMAL_DATA, i),
>>   				    (dword + i), NULL);
> [Severity: High]
> This is a pre-existing issue, but does this code create an unaligned memory
> access?
>
> In get_mc_temp(), the variable dword is initialized as:
>
>      u32 *dword = (u32 *)hwmon->temp.value;
>
> Since the value array is located at offset 10 in struct
> xe_hwmon_thermal_info, this cast creates a misaligned 32-bit pointer.
>
> When (dword + i) is passed to xe_pcode_read(), an unaligned 32-bit store
> occurs. On strict-alignment architectures, this could cause an alignment
> fault and kernel panic.
>
> Because the temp1_input sysfs attribute is world-readable, could this allow
> an unprivileged local user to trigger a denial of service?
This shall be addressed in next revision
>>   		if (ret)