qemu-system-aarch64 shows black framebuffer window on minimal bare metal example on SDL but not on VNC

QEMU v2.12.0, Ubuntu 18.04 host.

Build QEMU and the bare metal image exactly as described at: https://raspberrypi.stackexchange.com/revisions/85135/4 with:

Then cd into example 09_framebuffer.

Now if I do:

../../qemu/aarch64-softmmu/qemu-system-aarch64 -M raspi3 -kernel kernel8.img -serial stdio

the SDL window shows up black.

However, if I use VNC:

../../qemu/aarch64-softmmu/qemu-system-aarch64 -M raspi3 -kernel kernel8.img -serial stdio -vnc :1
vinagre :5901

an image of Homer Simpson appears as expected.

Therefore, I think this must be a QEMU / SDL bug instead of the repository, since we get different behaviors with `-vnc` and with SDL.

Things that work:

- https://github.com/cirosantilli/linux-kernel-module-cheat/tree/741f5215e9515c0d7179671f49fe1781f94e70e3#graphic-mode-arm which shows the Penguin with the Linux kernel, after hacking that repo up to use the exact same QEMU executable as reported here
- the UART examples on the image repo: https://github.com/bztsrc/raspi3-tutorial/tree/9e5611a624b3037788d5b29d951304938bff13ea/05_uart0

Works for me with both the GTK display and '-display sdl' with current head-of-git QEMU...


Hi; I'm moving this bug to 'incomplete', because I was never able to repro it -- gtk and sdl displays both worked for me. 


[Expired for QEMU because there has been no activity for 60 days.]