[PATCH] drm/amd/display: Fix null check of pipe_ctx->plane_state for update_dchubp_dpp

[Alex Hung]

Reviewed-by: Alex Hung <alex.hung at amd.com>

On 4/30/25 08:11, Melissa Wen wrote:
> Similar to commit 6a057072ddd1 ("drm/amd/display: Fix null check for
> pipe_ctx->plane_state in dcn20_program_pipe") that addresses a null
> pointer dereference on dcn20_update_dchubp_dpp. This is the same
> function hooked for update_dchubp_dpp in dcn401, with the same issue.
> Fix possible null pointer deference on dcn401_program_pipe too.
> 
> Fixes: 63ab80d9ac0ad ("drm/amd/display: DML2.1 Post-Si Cleanup")
> Signed-off-by: Melissa Wen <mwen at igalia.com>
> ---
>   drivers/gpu/drm/amd/display/dc/hwss/dcn401/dcn401_hwseq.c | 6 +++---
>   1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/gpu/drm/amd/display/dc/hwss/dcn401/dcn401_hwseq.c b/drivers/gpu/drm/amd/display/dc/hwss/dcn401/dcn401_hwseq.c
> index 8611eb9607df..c8c8a17ff183 100644
> --- a/drivers/gpu/drm/amd/display/dc/hwss/dcn401/dcn401_hwseq.c
> +++ b/drivers/gpu/drm/amd/display/dc/hwss/dcn401/dcn401_hwseq.c
> @@ -2259,9 +2259,9 @@ void dcn401_program_pipe(
>   				dc->res_pool->hubbub, pipe_ctx->plane_res.hubp->inst, pipe_ctx->hubp_regs.det_size);
>   	}
>   
> -	if (pipe_ctx->update_flags.raw ||
> -		(pipe_ctx->plane_state && pipe_ctx->plane_state->update_flags.raw) ||
> -		pipe_ctx->stream->update_flags.raw)
> +	if (pipe_ctx->plane_state && (pipe_ctx->update_flags.raw ||
> +	    pipe_ctx->plane_state->update_flags.raw ||
> +	    pipe_ctx->stream->update_flags.raw))
>   		dc->hwss.update_dchubp_dpp(dc, pipe_ctx, context);
>   
>   	if (pipe_ctx->plane_state && (pipe_ctx->update_flags.bits.enable ||