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

[Alex Deucher]

Acked-by: Alex Deucher <alexander.deucher at amd.com>

Can you add a fixes: tag?

Alex

On Mon, Sep 13, 2021 at 3:11 PM Nicholas Kazlauskas
<nicholas.kazlauskas at amd.com> 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 at amd.com>
> Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas at amd.com>
> ---
>  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);
>
> --
> 2.25.1
>