[PATCH v3] drm/amd/pm: parse pp_handle under appropriate conditions

[Mario Limonciello]

On 5/5/23 22:48, Guchun Chen wrote:
> amdgpu_dpm_is_overdrive_supported is a common API across all
> asics, so we should cast pp_handle into correct structure
> under different power frameworks.
>
> v2: using return directly to simplify code
> v3: SI asic does not carry od_enabled member in pp_handle, and update Fixes tag
>
> Link: https://gitlab.freedesktop.org/drm/amd/-/issues/2541
> Fixes: eb4900aa4c49("drm/amdgpu: Fix kernel NULL pointer dereference in dpm functions")
> Suggested-by: Mario Limonciello <mario.limonciello at amd.com>
> Signed-off-by: Guchun Chen <guchun.chen at amd.com>
Reviewed-by: Mario Limonciello <mario.limonciello at amd.com>
> ---
>   drivers/gpu/drm/amd/pm/amdgpu_dpm.c | 20 +++++++++++++-------
>   1 file changed, 13 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/pm/amdgpu_dpm.c b/drivers/gpu/drm/amd/pm/amdgpu_dpm.c
> index 300e156b924f..86246f69dbe1 100644
> --- a/drivers/gpu/drm/amd/pm/amdgpu_dpm.c
> +++ b/drivers/gpu/drm/amd/pm/amdgpu_dpm.c
> @@ -1460,15 +1460,21 @@ int amdgpu_dpm_get_smu_prv_buf_details(struct amdgpu_device *adev,
>   
>   int amdgpu_dpm_is_overdrive_supported(struct amdgpu_device *adev)
>   {
> -	struct pp_hwmgr *hwmgr = adev->powerplay.pp_handle;
> -	struct smu_context *smu = adev->powerplay.pp_handle;
> +	if (is_support_sw_smu(adev)) {
> +		struct smu_context *smu = adev->powerplay.pp_handle;
> +
> +		return (smu->od_enabled || smu->is_apu);
> +	} else {
> +		struct pp_hwmgr *hwmgr;
>   
> -	if ((is_support_sw_smu(adev) && smu->od_enabled) ||
> -	    (is_support_sw_smu(adev) && smu->is_apu) ||
> -		(!is_support_sw_smu(adev) && hwmgr->od_enabled))
> -		return true;
> +		/* SI asic does not carry od_enabled */
> +		if (adev->family == AMDGPU_FAMILY_SI)
> +			return false;
>   
> -	return false;
> +		hwmgr = (struct pp_hwmgr *)adev->powerplay.pp_handle;
> +
> +		return hwmgr->od_enabled;
> +	}
>   }
>   
>   int amdgpu_dpm_set_pp_table(struct amdgpu_device *adev,