Hi Gerd,

I have tried what you told me.

1. Turn off fbdev support:

static bool enable_fbdev = false;

2. configure a serial console:

- add something like "console=ttyS0, 9600n8" to the grub menuentry

- add a start parameter to qemu when start the virtual machine "-serial pty"

- got a redirected device like "char device redirected to /dev/pts/2"

- see the vritual machine's kernel messages in a host console by typing "cat /dev/pts/2"

And stuck in dark but got the messages bellow:

saned disabled; edit /etc/default/saned

[ ok ] Starting network connection manager: NetworkManager.

[ ok ] Starting Common Unix Printing System: cupsd.

The serial console messages also stop here, no other output.

I just don't know if I did the right thing, if I did something wrong, I would be appreaciate if

you show me.

Best Regards,

Zhao

On Wed, Jun 10, 2015 at 4:15 PM, John Hunter <zhjwpku@gmail.com> wrote:

Thanks for the information, I will try that : )

On Wed, Jun 10, 2015 at 4:04 PM, Gerd Hoffmann <kraxel@redhat.com> wrote:
Hi,

> As far as I know, the convertion got some problem, and after I
> add the bochs driver when I boot the qemu VM, it just can not
> start up, works fine if I delete bochs-drm.ko from it's directory.

With fbdev enabled alot initialization happens with some important
console lock taken, which has the effect that you don't see any kernel
messages until it all succeeded. If it doesn't succeed you are stuck in
the dark. Guess this is what happened ...

So, configure a serial console for your virtual machine.
Turn off fbdev support (bochs_drm has a module option for that).
That most likely gives you a clue where things blow up.

Then get X11 running.
kmscon is a nice test too.
When all this works try turning fbdev back on.

HTH,
Gerd

--
Best regards
Junwang Zhao
Microprocessor Research and Develop Center
Department of Computer Science &Technology
Peking University
Beijing, 100871, PRC

Best regards

Junwang Zhao

Microprocessor Research and Develop Center

Department of Computer Science &Technology

Peking University

Beijing, 100871, PRC