overlay_qsv cannot burn graphic subtitles on windows

[Yifei]

Summary of the bug:
Tried to burn dvdsub subtitles with this command
ffmpeg.exe -c:v h264_qsv -hwaccel qsv -i file:"E:\Movies\魔女宅急便 (1989)\魔女宅急便 (1989) h264-720p AAC-2ch.mkv" -map_metadata -1 -map_chapters -1 -threads 0 -map 0:0 -map 0:1 -codec:v:0 h264_qsv -preset 7 -look_ahead 0 -b:v 3073050 -maxrate 3073050 -bufsize 6146100 -profile:v high -level 4.1 -copyts -filter_complex "[0:2]scale=1280:690,hwupload=extra_hw_frames=64[sub];[0:0][sub]overlay_qsv=x=(W-w)/2:y=(H-h)/2,scale_qsv=format=nv12" -start_at_zero -vsync -1 -codec:a:0 libmp3lame -ac 2 -ab 192000 -copyts -avoid_negative_ts disabled -f hls -max_delay 5000000 -hls_time 3 -individual_header_trailer 0 -hls_segment_type mpegts -start_number 0 -hls_segment_filename "C:\Users\NAS\AppData\Local\Jellyfin\transcodes\transcodes\1dca7b37cb19f0ea101c7ef1bf1719e2%d.ts" -hls_playlist_type vod -hls_list_size 0 -y "C:\Users\NAS\AppData\Local\Jellyfin\transcodes\transcodes\1dca7b37cb19f0ea101c7ef1bf1719e2.m3u8"

log shows:
[AVHWFramesContext @ 0000022721410380] Unsupported pixel format: bgra
[AVHWFramesContext @ 0000022721410380] Error creating an internal frame pool
[AVHWFramesContext @ 00000227214116c0] Error initializing a child frames context
[AVHWFramesContext @ 00000227214116c0] Error creating an internal frame pool
[Parsed_hwupload_1 @ 00000227216dc4c0] Failed to configure output pad on Parsed_hwupload_1
Error reinitializing filters!
Failed to inject frame into filter network: Invalid argument
Error while processing the decoded data for stream #0:0
[libmp3lame @ 0000022720e74d00] 3 frames left in the queue on closing
Conversion failed!

[Yifei]

ffmpeg version git-2020-03-30-8d019db Copyright (c) 2000-2020 the FFmpeg developers

built with gcc 9.3.1 (GCC) 20200328
configuration: --disable-static --enable-shared --enable-gpl --enable-version3 --enable-sdl2 --enable-fontconfig --enable-gnutls --enable-iconv --enable-libass --enable-libdav1d --enable-libbluray --enable-libfreetype --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libsrt --enable-libtheora --enable-libtwolame --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libzimg --enable-lzma --enable-zlib --enable-gmp --enable-libvidstab --enable-libvmaf --enable-libvorbis --enable-libvo-amrwbenc --enable-libmysofa --enable-libspeex --enable-libxvid --enable-libaom --enable-libmfx --enable-ffnvcodec --enable-cuda-llvm --enable-cuvid --enable-d3d11va --enable-nvenc --enable-nvdec --enable-dxva2 --enable-avisynth --enable-libopenmpt --enable-amf
libavutil 56. 42.102 / 56. 42.102
libavcodec 58. 77.101 / 58. 77.101
libavformat 58. 42.100 / 58. 42.100
libavdevice 58. 9.103 / 58. 9.103
libavfilter 7. 77.101 / 7. 77.101
libswscale 5. 6.101 / 5. 6.101
libswresample 3. 6.100 / 3. 6.100
libpostproc 55. 6.100 / 55. 6.100