Regression: CPU side format conversions don't work anymore

[eero-t]

Setup:

• HW: GEN9 (SkullCanyon)
• OS: Ubuntu 20.04
• Driver stack: latest Git version builds of drm-tip kernel, libdrm, gmmlib, libva, media-driver and FFmpeg

media-driver regressed between following commits:

• 2020-07-30 08:21:31 a732aa1: [VP] Refine VP HW Filter
• 2020-08-02 11:43:13 8aa1d74: media: don't advertise AV1 decoding if the platform doesn't support it

CPU side format conversions don't anymore work, for example:
ffmpeg -y -hwaccel vaapi -vaapi_device /dev/dri/renderD128 -hwaccel_output_format vaapi -i <AVC-file>.264 -vf hwdownload,format=uyvy422 -f null -

Gives now following error, since the latter commit:

[AVHWFramesContext @ 0x7f2f7c0581c0] Failed to read image from surface 0x1c: 2 (resource allocation failed).
[hwdownload @ 0x563a7e003d00] Failed to download frame: -5.
Error while filtering: Input/output error
Failed to inject frame into filter network: Input/output error
Error while processing the decoded data for stream #0:0
Conversion failed!

Whereas it works fine with the former commit (and AFAIK has worked fine since bug #757 was fixed).

Same issue happens for all CPU side format conversions, marked with "O" in the table here: https://trac.ffmpeg.org/ticket/7691#comment:9

[XinfengZhang]

yes, I reproduced the issue, but it already been fixed with latest driver. I tried a51bd7c.

[eero-t]

Thanks, verified with a51bd7c.