Black screen, UI lock up, when starting Xserver,

[Adam Jackson]

On Fri, 2018-09-14 at 18:46 +0100, John Talbut wrote:
> Thanks Adam
> 
> If I boot to runlevel 3, log into tty1 as root and run 'X -retro' the UI
> locks up.

When this happens, does VT switch still work? Can you hit control-alt-
backspace to terminate the server? If yes (and the answer to both
should be the same) then the server is "alive" but something about
changing the video mode has gone awry, so that where the server is
drawing is not where the hardware is looking.

This would probably be a kernel bug, probably in the gma500 driver,
which is not a great place to be as the driver is essentially
unmaintained afaik. dri-devel at lists.freedesktop.org would be the most
likely place to find help, and they would probably want to see dmesg
from a boot with 'drm.debug=0x7' on the kernel command line for the
details of the attempted modeset, but I wouldn't get my hopes up.

Alternatively, you can try booting with 'nomodeset' on the kernel
command line, which should disable the gma500 driver. X will then use
the vesa driver, which is normally not a great place to be either, but
the gma500 driver's only real advantage over vesa is hotplug support as
neither one has any hardware acceleration.

> If I boot to runlevel 3, log into tty2 as a user and run 'X -retro' the
> tty stays live and I get some messages:

This is just the security checks in the server preventing you from
running it as a regular user (on the theory that, if anyone on the
system could start a display server, you could spoof an existing
session).

> It is a bit difficult to send whole log files as I do not have an email
> client on the machine without the desktop.

If you can ssh in, you can scp files out...

- ajax