Re: kern/59721: qemu VM's blackscreen over VNC wth -machine q35

[Taylor R Campbell <riastradh%NetBSD.org@localhost>]

Upstream bug report:

Black screen in Windows XP
https://gitlab.com/qemu-project/qemu/-/issues/2608

> This can be reduced to:
> 
> ./qemu-system-x86_64 -machine q35,smm=off,accel=kvm -vga std -cdrom winxp.iso
> 
> The key here is smm=off.  Without it, the thing just works.
> 
> The behavior change has been introduced by (bisection points to)
> commit b07bf7b7 (before this commit, winXP guest shows text-mode
> output fine, after - only graphics mode is shown).