[REGRESSION] DG2 Video Processing broken with CCS load balancing change

The patch series Disable automatic load CCS load balancing is causing issues with certain Video Processing functions on DG2 GPUs. The driver reports a Fence expiration time out error when trying to use the HDR10 Tone Mapping provided by the Intel Media Driver for VAAPI.

We have received multiple reports of this issue in our downstream repository: https://github.com/jellyfin/jellyfin/issues/11380

This series is applied to Linux versions >=6.6.26 and >=6.8.5.

Our users have verified that reverting this series or using an older kernel indeed resolves the Tone Mapping issue.

To reproduce the problem, please run the system with affected kernel version, then download our ffmpeg and execute the following command:

./ffmpeg -analyzeduration 200M -init_hw_device vaapi=va:,kernel_driver=i915,driver=iHD -init_hw_device qsv=qs@va -filter_hw_device qs -hwaccel vaapi -hwaccel_output_format vaapi -autorotate 0 -i file:"ANY_HDR_VIDEO.mp4" -autoscale 0 -codec:v:0 h264_qsv -low_power 1 -vf "setparams=color_primaries=bt2020:color_trc=smpte2084:colorspace=bt2020nc,procamp_vaapi=b=16:c=1,tonemap_vaapi=format=nv12:p=bt709:t=bt709:m=bt709:extra_hw_frames=32,hwmap=derive_device=qsv,format=qsv" -codec:a:0 copy testout.mp4

Using debian and dpkg -i the deb, then use sudo apt -f install to install all missing dependencies is recommended as it will prevent potential API version mismatch for OneVPL.

The ffmpeg command could either be very slow or failed directly, and you will see error like this in dmesg: Fence expiration time out i915-0000:29:00.0:ffmpeg[18950]:2!

As some distros are already pushing updates to the affected kernel versions, and Ubuntu Noble(next LTS) will be based on 6.8, we expect this will have a larger impact.