Well, I figured out the problem.  I was having a problem with XFree86 2.1 and
-current, where xdm would let me log in once, but when logging out would hang
the console.  The problem was a bug in the Mach32 and S3 servers.  The patch
for this is below ( via the folks at XFree86 ) and has been fixed in 2.1.1.  So
if you are having this same problem with the Mach32 or S3 servers, either apply
this patch or get 2.1.1.

Brian Moore
ziff@eecs.umich.edu

From: David Dawes <dawes@physics.su.OZ.AU>
Subject: Re: Problem with xdm on NetBSD-current and XFree 2.1

>I been having the problem that is listed below and have not been able to
>diagnose it.  Other people have had xdm running on NetBSD-current, but at least
>one other person has had this same problem.  I have the sources that I dragged
>down and everything works, but xdm.  I can help debug this problem, but I'll
>need some pointers on where to look.

This sounds like a problem someone found and fixed on the freebsd-hackers
list.  You don't say which server you are using, but the fix was to
change the following in the server's EnterLeaveVT() function from:

    pspix = (PixmapPtr)pScreen->devPrivate;

to:

    if (!x386Exiting && !x386Resetting)
        pspix = (PixmapPtr)pScreen->devPrivate;

It looks like the server is dereferencing an invalid pointer at exit/reset.
I don't know why this problem hasn't shown up before (or maybe it has?).

Let me know if this fix helps.  I plan to include it in 2.1.1.

David

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