Mattias,
Cédric, can you try with the above patch and/or
crash seems gone.
share more details of your setup so I can verify
You will need a Linnux powerpc or powerpc64 image for mac machines,
which are not common now days, or MacOS images. My debian images
are big. I will try to build you a small one for more tests.
Grab :
https://cdimage.debian.org/cdimage/ports/10.0/powerpc/iso-cd/debian-10.0-powerpc-NETINST-1.iso
and run :
qemu-system-ppc -M mac99 -cpu g4 -cdrom debian-10.0.0-powerpc-NETINST-1.iso
-nographic -boot d
Thanks,
C.