nvidia-drm does not support DRM_IOCTL_MODE_GETRESOURCES?

The reason I concern about this is that I found plymouth shows only a blank screen during booting using nvidia-410 driver which was installed from CUDA repo on Ubuntu 18.04. I reported a bug on launchpad to project plymouth (https://bugs.launchpad.net/ubuntu/+source/plymouth/+bug/1810815). As it isn’t assigned to anyone so far, I decided to dig a little by myself. Tracing plymouth’s log, I tracked down to libdrm’s drmModeGetResources(int fd). To verify this issue, I tried libdrm 2.4.91’s tests/modeprint utility on nvidia-drm. With detail logs added by myself, it shows the ioctl DRM_IOCTL_MODE_GETRESOURCES returns -1 with errno 22: Invalid argument.

So my question is, is this bug or nvidia-drm is designed not to support DRM_IOCTL_MODE_GETRESOURCES?

nvidia-bug-report.log (3.12 MB)


…and the answer to the OP question is?