Building with the attached random configuration file,
drivers/built-in.o: In function `vb2_fop_mmap':
(.text+0x30256b): undefined reference to `video_devdata'
drivers/built-in.o: In function `vb2_ioctl_expbuf':
(.text+0x3025b9): undefined reference to `video_devdata'
drivers/built-in.o: In function `vb2_ioctl_streamoff':
(.text+0x302639): undefined reference to `video_devdata'
drivers/built-in.o: In function `vb2_ioctl_streamon':
(.text+0x3026b9): undefined reference to `video_devdata'
drivers/built-in.o: In function `vb2_ioctl_dqbuf':
(.text+0x303094): undefined reference to `video_devdata'
drivers/built-in.o:(.text+0x3031f1): more undefined references to
`video_devdata' follow
drivers/built-in.o: In function `vb2_thread':
videobuf2-core.c:(.text+0x30396e): undefined reference to `v4l2_get_timestamp'
drivers/built-in.o: In function `vb2_ioctl_qbuf':
(.text+0x303aba): undefined reference to `video_devdata'
drivers/built-in.o: In function `vb2_ioctl_prepare_buf':
(.text+0x303c43): undefined reference to `video_devdata'
drivers/built-in.o: In function `vb2_ioctl_create_bufs':
(.text+0x3045e8): undefined reference to `video_devdata'
drivers/built-in.o: In function `vb2_ioctl_reqbufs':
(.text+0x304cb9): undefined reference to `video_devdata'
drivers/built-in.o: In function `_vb2_fop_release':
(.text+0x305067): undefined reference to `video_devdata'
drivers/built-in.o: In function `_vb2_fop_release':
(.text+0x305117): undefined reference to `v4l2_fh_release'
drivers/built-in.o: In function `vb2_fop_release':
(.text+0x305148): undefined reference to `video_devdata'
drivers/built-in.o: In function `__vb2_perform_fileio':
videobuf2-core.c:(.text+0x3059bb): undefined reference to `v4l2_get_timestamp'
drivers/built-in.o: In function `vb2_fop_write':
(.text+0x305b07): undefined reference to `video_devdata'
drivers/built-in.o: In function `vb2_fop_read':
(.text+0x305cae): undefined reference to `video_devdata'
drivers/built-in.o: In function `vb2_poll':
(.text+0x305e11): undefined reference to `video_devdata'
drivers/built-in.o: In function `vb2_poll':
(.text+0x305e6d): undefined reference to `v4l2_event_pending'
drivers/built-in.o: In function `vb2_fop_poll':
(.text+0x3063f9): undefined reference to `video_devdata'
make: *** [vmlinux] Error 1