Request for explanation of error message

[Mike Marchywka]

On Mon, Jul 29, 2019 at 11:41:13AM +0200, Oliver Grawert wrote:
> hi,
> Am Montag, den 29.07.2019, 06:12 +0800 schrieb Bret Busby:
> > > > "
> > > > bret at bret-MD34045-2521:~$ sudo head -25 /var/log/lightdm/x-0.log
> > > > 
> > > > X.Org X Server 1.19.6
> > > > Release Date: 2017-12-20
> > > > X Protocol Version 11, Revision 0
> > > > Build Operating System: Linux 4.4.0-148-generic x86_64 Ubuntu
> > > > Current Operating System: Linux bret-MD34045-2521 4.15.0-55-
> > > > generic
> > > > #60-Ubuntu SMP Tue Jul 2 18:22:20 UTC 2019 x86_64
> > > > Kernel command line: BOOT_IMAGE=/boot/vmlinuz-4.15.0-55-generic
> > > > root=UUID=1d3945d6-b596-4d57-8151-d2eef48a56b8 ro quiet splash
> > > > vt.handoff=1
> > > > Build Date: 03 June 2019  08:10:35AM
> > > > xorg-server 2:1.19.6-1ubuntu4.3 (For technical support please see
> > > > http://www.ubuntu.com/support)
> > > > Current version of pixman: 0.34.0
> > > > 	Before reporting problems, check http://wiki.x.org
> > > > 	to make sure that you have the latest version.
> > > > Markers: (--) probed, (**) from config file, (==) default
> > > > setting,
> > > > 	(++) from command line, (!!) notice, (II) informational,
> > > > 	(WW) warning, (EE) error, (NI) not implemented, (??) unknown.
> > > > (==) Log file: "/var/log/Xorg.0.log", Time: Mon Jul 29 03:29:50
> > > > 2019
> > > > (==) Using system config directory "/usr/share/X11/xorg.conf.d"
> > > > xf86EnableIOPorts: failed to set IOPL for I/O (Operation not
> > > > permitted)
> > > > _XSERVTransSocketUNIXAccept: accept() failed
> > > > _XSERVTransSocketUNIXAccept: accept() failed
> > > > _XSERVTransSocketUNIXAccept: accept() failed
> > > > _XSERVTransSocketUNIXAccept: accept() failed
> > > > _XSERVTransSocketUNIXAccept: accept() failed
> > > > _XSERVTransSocketUNIXAccept: accept() failed
> > > > _XSERVTransSocketUNIXAccept: accept() failed
> > > > "
> > > > 
> > > > that last line is an endless loop.
> > > 
> ...
> > Thanks to #openbsd's epony and oldlaptop, the resolution is to:
> > 
> ... on openbsd ... which you are not running ;)
> 
> (and in general it is a bad idea to randomly change system defaults
> while you are debugging an issue *only you* seem to have ... this
> indicates that something you changed actually broke it ... this is
> rarely caused by a system config everyone else uses too)

With only two messages that both return google hits it seemed like
an ok place to start but many systems don't have anyone else using
them so it is hard to get much from that. 




> 
> the error indicates that there are some broken file permissions ... 
> 
>From ps it appeared to be running as root and later with lsof had
some reasonable number of open files. netstat showed some connections.

You can go through and check the dates on the config files but 
hopefully if you try to start it by hand with debug options,
either lightdm or X directly, you can get some idea
which files are most suspect. IIRC there was also a pci
error in this thread and you can see if anything triggers that.

There is probably a single user or recovery option if you get
a grub menu, select that one before it times out to normal boot.
You can use the prior ps output from your console command prompt,
iirc something like

/usr/sbin/lightdm

or the x command,

ps ax | grep lightdm
 1191 ?        SLsl   0:00 /usr/sbin/lightdm
 1243 tty7     Ssl+  79:47 /usr/lib/xorg/Xorg -core :0 -seat seat0 -auth /var/run/lightdm/root/:0 -nolisten tcp vt7 -novtswitch
 1332 ?        Sl     0:00 lightdm --session-child 12 19

if you "man lightdm" it seems to have a debug mode
and Xorg has a verbose option. You can check the dates on
any files they try to open again IIRC your logs exploded
between the 16th and 22nd or something. 



> what type of graphical session do you run ...
> 
> could it be that you ran some graphical app (for example a file
> manager) as root that was not designed for this (so it changed the
> permissions of a (potentially hidden) file to be only root readable
> while it is normally used/written to by a user) ... 
> 
> do you have an ~/.xinitrc in your home dir ?
> 
> did you ever edit /etc/X11/xorg.xonf (either manually or by using a
> tool like nvidia-config)
> 
> do you have any third party stuff installed from a PPA or elsewhere
> that could have replaced system libs or apps in a broken way ... (note
> that .deb packages give their creator 100% root access to your system,
> installing foreign packages is always a matter of trust here (this is
> why snap packages exist btw))
> 
> ciao
> 	oli



-- 

mike marchywka
306 charles cox
canton GA 30115
USA, Earth 
marchywka at hotmail.com
404-788-1216
ORCID: 0000-0001-9237-455X