Re: [PATCH 6.10 090/263] drm/amdgpu/pm: Fix the param type of set_power_profile_mode

[Jiri Slaby <jirislaby@kernel.org>]

FTR:
Delivery has failed to these recipients or groups:
Ma Jun (Jun.Ma2@amd.com)
The email address you entered couldn't be found

So the author of the patch CANNOT respond. Anyone else?

On 19. 08. 24, 9:49, Jiri Slaby wrote:
> On 12. 08. 24, 18:01, Greg Kroah-Hartman wrote:
>> 6.10-stable review patch.  If anyone has any objections, please let me 
>> know.
>>
>> ------------------
>>
>> From: Ma Jun <Jun.Ma2@amd.com>
>>
>> [ Upstream commit f683f24093dd94a831085fe0ea8e9dc4c6c1a2d1 ]
>>
>> Function .set_power_profile_mode need an array as input
>> parameter.
> 
> Which one and why?
> 
> static int smu_bump_power_profile_mode(struct smu_context *smu,
>                                             long *param,
>                                             uint32_t param_size)
> 
>    int (*set_power_profile_mode)(struct smu_context *smu, long *input, 
> uint32_t size);
> 
> static int pp_set_power_profile_mode(void *handle, long *input, uint32_t 
> size)
> 
>    int (*set_power_profile_mode)(struct pp_hwmgr *hwmgr, long *input, 
> uint32_t size);
> 
> static int smu10_set_power_profile_mode(struct pp_hwmgr *hwmgr, long 
> *input, uint32_t size)
> {
>          int workload_type = 0;
>          int result = 0;
> 
>          if (input[size] > PP_SMC_POWER_PROFILE_COMPUTE) {
> 
> 
> There is absolutely no problem doing input[0] when a pointer to a local 
> non-array variable is passed, is it?
> 
>> So define variable workload as an array to fix
>> the below coverity warning.
> 
> This very much looks like one of many Coverity false positives.
> 
>> "Passing &workload to function hwmgr->hwmgr_func->set_power_profile_mode
>> which uses it as an array. This might corrupt or misinterpret adjacent
>> memory locations"
> 
> Care to explain how this fixes anything but a Coverity false positive? 
> Why was this included in a stable tree at all?
> 
>> Signed-off-by: Ma Jun <Jun.Ma2@amd.com>
>> Acked-by: Alex Deucher <alexander.deucher@amd.com>
>> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
>> Signed-off-by: Sasha Levin <sashal@kernel.org>
> ...
>> --- a/drivers/gpu/drm/amd/pm/powerplay/amd_powerplay.c
>> +++ b/drivers/gpu/drm/amd/pm/powerplay/amd_powerplay.c
>> @@ -929,7 +929,7 @@ static int pp_dpm_switch_power_profile(void *handle,
>>           enum PP_SMC_POWER_PROFILE type, bool en)
>>   {
>>       struct pp_hwmgr *hwmgr = handle;
>> -    long workload;
>> +    long workload[1];
> 
> This only obfuscates the code. So please revert this if you cannot 
> explain what real issue this actually fixes.
> 
>>       uint32_t index;
>>       if (!hwmgr || !hwmgr->pm_en)
>> @@ -947,12 +947,12 @@ static int pp_dpm_switch_power_profile(void 
>> *handle,
>>           hwmgr->workload_mask &= ~(1 << hwmgr->workload_prority[type]);
>>           index = fls(hwmgr->workload_mask);
>>           index = index > 0 && index <= Workload_Policy_Max ? index - 
>> 1 : 0;
>> -        workload = hwmgr->workload_setting[index];
>> +        workload[0] = hwmgr->workload_setting[index];
>>       } else {
>>           hwmgr->workload_mask |= (1 << hwmgr->workload_prority[type]);
>>           index = fls(hwmgr->workload_mask);
>>           index = index <= Workload_Policy_Max ? index - 1 : 0;
>> -        workload = hwmgr->workload_setting[index];
>> +        workload[0] = hwmgr->workload_setting[index];
>>       }
>>       if (type == PP_SMC_POWER_PROFILE_COMPUTE &&
>> @@ -962,7 +962,7 @@ static int pp_dpm_switch_power_profile(void *handle,
>>       }
>>       if (hwmgr->dpm_level != AMD_DPM_FORCED_LEVEL_MANUAL)
>> -        hwmgr->hwmgr_func->set_power_profile_mode(hwmgr, &workload, 0);
>> +        hwmgr->hwmgr_func->set_power_profile_mode(hwmgr, workload, 0);
>>       return 0;
>>   }
>> diff --git a/drivers/gpu/drm/amd/pm/powerplay/hwmgr/pp_psm.c 
>> b/drivers/gpu/drm/amd/pm/powerplay/hwmgr/pp_psm.c
>> index 1d829402cd2e2..f4bd8e9357e22 100644
>> --- a/drivers/gpu/drm/amd/pm/powerplay/hwmgr/pp_psm.c
>> +++ b/drivers/gpu/drm/amd/pm/powerplay/hwmgr/pp_psm.c
>> @@ -269,7 +269,7 @@ int psm_adjust_power_state_dynamic(struct pp_hwmgr 
>> *hwmgr, bool skip_display_set
>>                           struct pp_power_state *new_ps)
>>   {
>>       uint32_t index;
>> -    long workload;
>> +    long workload[1];
>>       if (hwmgr->not_vf) {
>>           if (!skip_display_settings)
>> @@ -294,10 +294,10 @@ int psm_adjust_power_state_dynamic(struct 
>> pp_hwmgr *hwmgr, bool skip_display_set
>>       if (hwmgr->dpm_level != AMD_DPM_FORCED_LEVEL_MANUAL) {
>>           index = fls(hwmgr->workload_mask);
>>           index = index > 0 && index <= Workload_Policy_Max ? index - 
>> 1 : 0;
>> -        workload = hwmgr->workload_setting[index];
>> +        workload[0] = hwmgr->workload_setting[index];
>> -        if (hwmgr->power_profile_mode != workload && 
>> hwmgr->hwmgr_func->set_power_profile_mode)
>> -            hwmgr->hwmgr_func->set_power_profile_mode(hwmgr, 
>> &workload, 0);
>> +        if (hwmgr->power_profile_mode != workload[0] && 
>> hwmgr->hwmgr_func->set_power_profile_mode)
>> +            hwmgr->hwmgr_func->set_power_profile_mode(hwmgr, 
>> workload, 0);
>>       }
>>       return 0;
>> diff --git a/drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c 
>> b/drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c
>> index e1796ecf9c05c..06409133b09b1 100644
>> --- a/drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c
>> +++ b/drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c
>> @@ -2220,7 +2220,7 @@ static int smu_adjust_power_state_dynamic(struct 
>> smu_context *smu,
>>   {
>>       int ret = 0;
>>       int index = 0;
>> -    long workload;
>> +    long workload[1];
>>       struct smu_dpm_context *smu_dpm_ctx = &(smu->smu_dpm);
>>       if (!skip_display_settings) {
>> @@ -2260,10 +2260,10 @@ static int 
>> smu_adjust_power_state_dynamic(struct smu_context *smu,
>>           smu_dpm_ctx->dpm_level != 
>> AMD_DPM_FORCED_LEVEL_PERF_DETERMINISM) {
>>           index = fls(smu->workload_mask);
>>           index = index > 0 && index <= WORKLOAD_POLICY_MAX ? index - 
>> 1 : 0;
>> -        workload = smu->workload_setting[index];
>> +        workload[0] = smu->workload_setting[index];
>> -        if (smu->power_profile_mode != workload)
>> -            smu_bump_power_profile_mode(smu, &workload, 0);
>> +        if (smu->power_profile_mode != workload[0])
>> +            smu_bump_power_profile_mode(smu, workload, 0);
>>       }
>>       return ret;
>> @@ -2313,7 +2313,7 @@ static int smu_switch_power_profile(void *handle,
>>   {
>>       struct smu_context *smu = handle;
>>       struct smu_dpm_context *smu_dpm_ctx = &(smu->smu_dpm);
>> -    long workload;
>> +    long workload[1];
>>       uint32_t index;
>>       if (!smu->pm_enabled || !smu->adev->pm.dpm_enabled)
>> @@ -2326,17 +2326,17 @@ static int smu_switch_power_profile(void *handle,
>>           smu->workload_mask &= ~(1 << smu->workload_prority[type]);
>>           index = fls(smu->workload_mask);
>>           index = index > 0 && index <= WORKLOAD_POLICY_MAX ? index - 
>> 1 : 0;
>> -        workload = smu->workload_setting[index];
>> +        workload[0] = smu->workload_setting[index];
>>       } else {
>>           smu->workload_mask |= (1 << smu->workload_prority[type]);
>>           index = fls(smu->workload_mask);
>>           index = index <= WORKLOAD_POLICY_MAX ? index - 1 : 0;
>> -        workload = smu->workload_setting[index];
>> +        workload[0] = smu->workload_setting[index];
>>       }
>>       if (smu_dpm_ctx->dpm_level != AMD_DPM_FORCED_LEVEL_MANUAL &&
>>           smu_dpm_ctx->dpm_level != 
>> AMD_DPM_FORCED_LEVEL_PERF_DETERMINISM)
>> -        smu_bump_power_profile_mode(smu, &workload, 0);
>> +        smu_bump_power_profile_mode(smu, workload, 0);
>>       return 0;
>>   }
> 
> thanks,

-- 
js
suse labs