I’ve built ffmpeg, but QSV seems broken on Ivy Bridge

I have built ffmpeg from source, based on this tutorial.

I had to modify it a bit, due to having an old i7 CPU and ffmpeg couldn’t initialize the decoder, and this thread states “Intel-Media-Driver” is not suitable for older i7s, I had to use intel-vaapi-driver.

I have recompiled ffmpeg. My vainfo:

$ vainfo
Trying display: drm
libva info: VA-API version 1.17.0
libva info: Trying to open /usr/local/lib/dri/iHD_drv_video.so
libva info: va_openDriver() returns -1
libva info: Trying to open /usr/local/lib/dri/i965_drv_video.so
libva info: Found init function __vaDriverInit_1_17
libva info: va_openDriver() returns 0
vainfo: VA-API version: 1.17 (libva 2.17.0.pre1)
vainfo: Driver version: Intel i965 driver for Intel(R) Ivybridge Desktop - 2.4.0.pre1 (2.3.0-35-gab755cb)
vainfo: Supported profile and entrypoints
      VAProfileMPEG2Simple            : VAEntrypointVLD
      VAProfileMPEG2Simple            : VAEntrypointEncSlice
      VAProfileMPEG2Main              : VAEntrypointVLD
      VAProfileMPEG2Main              : VAEntrypointEncSlice
      VAProfileH264ConstrainedBaseline: VAEntrypointVLD
      VAProfileH264ConstrainedBaseline: VAEntrypointEncSlice
      VAProfileH264Main               : VAEntrypointVLD
      VAProfileH264Main               : VAEntrypointEncSlice
      VAProfileH264High               : VAEntrypointVLD
      VAProfileH264High               : VAEntrypointEncSlice
      VAProfileH264StereoHigh         : VAEntrypointVLD
      VAProfileVC1Simple              : VAEntrypointVLD
      VAProfileVC1Main                : VAEntrypointVLD
      VAProfileVC1Advanced            : VAEntrypointVLD
      VAProfileNone                   : VAEntrypointVideoProc
      VAProfileJPEGBaseline           : VAEntrypointVLD

FFMpeg decoders:

$ ffmpeg -decoders | grep qsv
ffmpeg version N-109368-gcc11afe502 Copyright (c) 2000-2022 the FFmpeg developers
  built with gcc 9 (Ubuntu 9.4.0-1ubuntu1~20.04.1)
  configuration: --prefix=/usr/local/ffmpeg --extra-cflags=-I/opt/intel/mediasdk/include --extra-ldflags=-L/opt/intel/mediasdk/lib --extra-ldflags=-L/opt/intel/mediasdk/plugins --enable-libmfx --enable-vaapi --enable-opencl --disable-debug --enable-libvorbis --enable-libvpx --enable-libdrm --enable-gpl --cpu=native --enable-libfdk-aac --enable-libx264 --enable-libx265 --extra-libs=-lpthread --enable-nonfree --enable-openssl
  libavutil      57. 43.100 / 57. 43.100
  libavcodec     59. 54.100 / 59. 54.100
  libavformat    59. 34.102 / 59. 34.102
  libavdevice    59.  8.101 / 59.  8.101
  libavfilter     8. 51.100 /  8. 51.100
  libswscale      6.  8.112 /  6.  8.112
  libswresample   4.  9.100 /  4.  9.100
  libpostproc    56.  7.100 / 56.  7.100
 V....D av1_qsv              AV1 video (Intel Quick Sync Video acceleration) (codec av1)
 V....D h264_qsv             H264 video (Intel Quick Sync Video acceleration) (codec h264)
 V....D hevc_qsv             HEVC video (Intel Quick Sync Video acceleration) (codec hevc)
 V....D mjpeg_qsv            MJPEG video (Intel Quick Sync Video acceleration) (codec mjpeg)
 V....D mpeg2_qsv            MPEG2VIDEO video (Intel Quick Sync Video acceleration) (codec mpeg2video)
 V....D vc1_qsv              VC1 video (Intel Quick Sync Video acceleration) (codec vc1)
 V....D vp8_qsv              VP8 video (Intel Quick Sync Video acceleration) (codec vp8)
 V....D vp9_qsv              VP9 video (Intel Quick Sync Video acceleration) (codec vp9)

However, running a simple hw decoder script:

ffmpeg -hwaccel qsv -c:v h264_qsv -i ...

Causes my an error:

[AVHWDeviceContext @ 0x5621dbd9f100] Failed to initialise VAAPI connection: -1 (unknown libva error).
Device creation failed: -5.
No device available for decoder: device type qsv needed for codec h264_qsv.

How can I build ffmpeg with QSV to support my CPU?