modeset.c shows justa black screen in QEMU aarch64 -device virtio-gpu-pci

[cirosantilli]

Worked on x86_64 however.

This is the precise setups: https://github.com/cirosantilli/linux-kernel-module-cheat/tree/a64b276e9c02719a3e620c75aaa1ec490b240851#drm

I have copoied modeset.c in that repo in tree: https://github.com/cirosantilli/linux-kernel-module-cheat/blob/16de55dd2f89ae44c1ee0fee1c39d23ee2b36b13/kernel_module/user/libdrm_modeset.c at revision: fad7c32

kmscube however worked fine for both x86_64 and aarch64, so maybe it is a bug here?

[marler8997]

Have the same issue. Note that I'm using virgl acceleration. The modeset example results in a black screen but the modeset-vsync and modeset-double-buffered work. I don't know how you got graphics to work with qemu on arm, I had to modify qemu to add the hardware panel to get it to work. In any case, my guess is this is an issue with qemu and not with this example.

[henke96]

Adding a call to drmModeDirtyFB() after drawing fixed this for me.