libva vpp aplha overlay not support 3840x2160?

[ljc]

on linux use libva, ffmpeg vaapi decode get a hw avframe, format is p010.

use libav overlay a bgra vasurface on  video surface.

pipeline paramater is:

VAProcPipelineParameterBuffer overlay_param{0};

VABlendState blend_state = {0};

blend_state.flags = VA_BLEND_PREMULTIPLIED_ALPHA;
blend_state.global_alpha = 1.0f;

VARectangle subrect= {0,0,1280,720};

overlay_param.surface = (VASurfaceID)(uintptr_t)subtitle_frame_->data[3];
overlay_param.output_background_color = 0x00000000;
overlay_param.surface_region = nullptr;
overlay_param.output_region = subrect;
overlay_param.filter_flags = VA_FRAME_PICTURE;
overlay_param.pipeline_flags = 0;
overlay_param.blend_state = &blend_state;

overlay_param.surface_color_standard =VAProcColorStandardSRGB;

overlay_param.output_color_standard =VAProcColorStandardBT2020;   //try other value like  VAProcColorStandardNone etc

source surface is smaller then 1920x1080;

target surface when 1920x1080, it work

when 3840x2160, not work.

my paramter have any problem? or hardware have limitation?

driver is : Driver version: Intel iHD driver for Intel(R) Gen Graphics - 25.2.2 (9741b50)