Re: Cannot login via xdm after fresh install

[Erkki Ruohtula <erkkiruohtula%yahoo.com@localhost>]

On Sun, 10 Sep 2017 19:43:04 +0300
Erkki Ruohtula <erkkiruohtula%yahoo.com@localhost> wrote:
> I did a fresh installation with NetBSD-7.1-amd64.iso in VirtualBox
> 5.1.26, mostly using defaults. I did enable xdm in the installer.
> Everything appeared to go smoothly, and the system now starts nicely
> X11, and shows the xdm login screen. The problem is I cannot get
> past that. If I enter the username root and its correct
> password, I get a dialog box labeled "Session Menu",
> with text "chooseSessionListWidget" and buttons under it,
> of which most are grayed except "Default/Fail Safe" and "Cancel".
> 
> I thought "Default/Fail Safe" would be the obvious choice, but if
> I hit it, I get a black screen, except for the console log window
> in lower right-hand corner. X11 seems to be still running, but
> it is impossible to do anything except reset the (virtual) machine.
> Is the fail safe  configuration missing? Should something
> special be chosen in the installer? (in other X11 installations
> I have seen it usually consist of starting twm and a xterm window).

I did some digging by enabling ssh and logging in. Apparently
the way NetBSD sets up xdm, it starts up /usr/X11R7/bin/xsm if the
user's directory does not contain .xsession. In my case it was
running:

USER  PID %CPU %MEM   VSZ  RSS TTY   STAT STARTED    TIME COMMAND
erkki  73  0.0  0.4 45440 4152 ?     Is    6:08PM    0:00.04 /usr/X11R7/bin/xsm

In the absence of per user configuration, xsm should start the
programs listed in a default file /etc/X11/xsm/system.xsm
which contains

twm
smproxy
xterm

but apparently it fails to do so. (All these programs do exist
in the installation).

The user's .xsession-errors contains only

_IceTransmkdir: ERROR: euid != 0,directory /tmp/.ICE-unix will not be created.

However, that directory did exist, and contains the subdirectory
srwxrwxrwx  1 erkki  wheel  0 Sep 17 18:08 /tmp/.ICE-unix/73

According to "top", xsm is in state "select", which I guess means
it is stuck waiting on some descriptors.

Next I tried if an X11 session can be obtained in the old way
without xsm: I added a minimal .xsession with the lines

twm &
xterm

and restarted the system. This worked as expected: I got a twm session.
So xsm seems to have some bug, which has the effect that currently
asking the installer to enable xdm results in a system where
the user cannot log in at the console.

Erkki