Re: [PATCH] drm/amd/display: Fix white screen page fault for gpuvm

[Harry Wentland <harry.wentland@amd.com>]

On 2021-09-13 15:11, Nicholas Kazlauskas wrote:
> [Why]
> The "base_addr_is_mc_addr" field was added for dcn3.1 support but
> pa_config was never updated to set it to false.
> 
> Uninitialized memory causes it to be set to true which results in
> address mistranslation and white screen.
> 
> [How]
> Use memset to ensure all fields are initialized to 0 by default.
> 
> Cc: Aaron Liu <aaron.liu@amd.com>
> Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>

Reviewed-by: Harry Wentland <harry.wentland@amd.com>

Harry

> ---
>  drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> index 53363728dbb..b0426bb3f2e 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> @@ -1125,6 +1125,8 @@ static void mmhub_read_system_context(struct amdgpu_device *adev, struct dc_phy_
>  	uint32_t agp_base, agp_bot, agp_top;
>  	PHYSICAL_ADDRESS_LOC page_table_start, page_table_end, page_table_base;
>  
> +	memset(pa_config, 0, sizeof(*pa_config));
> +
>  	logical_addr_low  = min(adev->gmc.fb_start, adev->gmc.agp_start) >> 18;
>  	pt_base = amdgpu_gmc_pd_addr(adev->gart.bo);
>  
>