Ubuntu 18.10 boot hangs with INTEL GRAPHICS at msg "Starting bpfilter"

[rtimai]

This is not a question, but I found no thread to report this bug and workaround on NON-NVIDIA-BASED systems:

Ubuntu 18.10, kernel 4.18.0-12-generic, GNOME Shell 3.30.1 on X11, after a Dec 9 update:

Boot hangs at message, "Starting bpfilter." Gnome Display Manager (login) fails to start. No keyboard response, tapping the power button just once immediately initiates power-down. Other users have reported successfully fixing this by removing nVidia drivers or disabling Wayland in GDM3 (uncommenting WaylandEnable=false in /etc/gdm3/custom.conf.)

However, my HP laptop runs Intel graphics, and has no nVidia drivers installed.

WORKAROUND
I selected Enable Networking in Recovery Mode, then Drop to Shell Prompt (root,) and ran

 apt update && apt install slim

to install SLiM display manager. the installation prompted me to choose SLiM or GDM as the default, I chose SLiM, and was able to login finally (after rebooting 50+ times.)

If you already have an alternate display manager installed, you can switch with "sudo dpkg-reconfigure gdm" and select the alt dm.

This will probably be just a provisional workaround for the "bpfilter hang" on non-nVidia systems if all the other suggested solutions didn't work for you. BTW, I also tried LightDM a former Ubuntu DM, but got the identical bootup hang.
---
ProblemType: Bug
ApportVersion: 2.20.10-0ubuntu13.1
Architecture: amd64
CurrentDesktop: GNOME
DistroRelease: Ubuntu 18.10
InstallationDate: Installed on 2018-05-07 (219 days ago)
InstallationMedia: Ubuntu 18.04 LTS "Bionic Beaver" - Release amd64 (20180426)
NonfreeKernelModules: wl
Package: gdm3 3.30.1-1ubuntu5
PackageArchitecture: amd64
ProcEnviron:
 TERM=xterm-256color
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_US.UTF-8
 SHELL=/bin/bash
ProcVersionSignature: Ubuntu 4.18.0-12.13-generic 4.18.17
Tags: cosmic
Uname: Linux 4.18.0-12-generic x86_64
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups: adm cdrom dip lpadmin plugdev sambashare sudo
_MarkForUpload: True
mtime.conffile..etc.gdm3.custom.conf: 2018-12-10T07:21:25.671742

[Daniel van Vugt (vanvugt)]

Please:

1. Run 'apport-collect 1808125' to send us more information about the system.

2. Take a photo of the problem if you can.

3. Run 'journalctl > journal.txt' and attach the file 'journal.txt' here.

4. Run 'lspci -k > lspcik.txt' and attach the file 'lspcik.txt' here.

[Daniel van Vugt (vanvugt)]

5. Reproduce the hang, and then on the very NEXT reboot (recovery mode) run this command:
   journalctl -b-1 > prevboot.txt
   and attach the file 'prevboot.txt' here.

[rtimai (rtimai)]

apport information

[rtimai (rtimai)]

apport information

[rtimai (rtimai)]

apport information

[Daniel van Vugt (vanvugt)]

I don't think "Starting bpfilter" will be related at all. Likely that's just the last message you happen to see before the hang occurs.

[rtimai (rtimai)]

I ran #journalctl -b-1 > prevboot.txt in Recovery Mode after a hung GDM3 login attampt, then re-enabled SLiM DM to log in. The upload of this file was taking forever, so, I checked, and it's 771.2 MB! I am attempting to re-upload it as a compressed file hp15-ay016nr_journal.tar.xz 10.8 MB.

[rtimai (rtimai)]

Unable to take screenshot of the boot hang (duh) so I copied verbatim the two lines that appear in a *backlit* black screen (not sure if the backlight makes a difference,) and added a note about changes in the power button behavior during boot time. This could be related to my removal of timeout delays in grub2.

I guess I could have taken a photo w the phone. Not worth the time.

[rtimai (rtimai)]

I'm sorry, I got confused between the full journal file and the previous boot journal file. This is the previous boot as requested. The huge compressed .xz file is the full journal.

#journalctl -b-1 > prevboot.txt

[rtimai (rtimai)]

This is a recent apt history log. Perhaps it may provide an extra clue to the cause. The boot failure began after the December 9 update.

[Daniel van Vugt (vanvugt)]

There are two main issues I can see:

1. The 'pixel-saver' extension may be causing some bugs so maybe remove it while debugging.

2. You haven't actually had a gdm3 boot attempt since 9 December. So the failures you are experiencing recently are from SLiM, which makes this bug invalid for gdm3.

I recommend reinstalling Ubuntu and if a problem occurs with a clean installation then run:

  ubuntu-bug gdm3

to create a new bug.

[Daniel van Vugt (vanvugt)]

Although that new log from comment #19 is more useful. It shows GDM repeatedly failing:

Dec 13 01:06:43 hp15-ay016nr systemd[1]: Starting GNOME Display Manager...
Dec 13 01:06:43 hp15-ay016nr generate-config[2068]: warning: Failed to read keyfile '/usr/share/gdm/dconf/90-debian-settings': Key file does not start with a group
Dec 13 01:06:43 hp15-ay016nr systemd[1]: gdm.service: Control process exited, code=exited status=1
Dec 13 01:06:43 hp15-ay016nr systemd[1]: gdm.service: Failed with result 'exit-code'.

Please next attach a copy of your file:
/usr/share/gdm/dconf/90-debian-settings

Please also follow these steps to search for crash information:
https://wiki.ubuntu.com/Bugs/Responses#Missing_a_crash_report_or_having_a_.crash_attachment

[rtimai (rtimai)]

Daniel, I want to thank you for the effort you are putting into this issue. I'm gratified that someone is taking this seriously. I look forward to seeing a *real* fix.

[rtimai (rtimai)]

No changes except to disable user list, prefer to enter my username.

[Daniel van Vugt (vanvugt)]

Ah, I think I see the problem. It's a syntax error in your 90-debian-settings. You need to also uncomment:

#[org/gnome/login-screen]

since it provides the context (group) information for:

disable-user-list=true

[rtimai (rtimai)]

Daniel, again thanks for your efforts. My replies in red below. --rti

On Thu, Dec 13, 2018 at 2:41 AM Daniel van Vugt <
<email address hidden>> wrote:

> There are two main issues I can see:
> 1. The 'pixel-saver' extension may be causing some bugs so maybe remove
> it while debugging.
>
*OK, will disable if not remove. Unable to test immediately, but will
report if any effect, probably this weekend.*

> 2. You haven't actually had a gdm3 boot attempt since 9 December. So the
> failures you are experiencing recently are from SLiM, which makes this
> bug invalid for gdm3.
>
*Have not had a GDM3 boot attempt because they all failed (40-50 times.) I
think the SLiM errors may be due to this dm "not requiring systemd." I'm
sure SLiM is not a good display manager for a system that relies on
systemd. For the time being, however, it's the only recourse that enables
me to log into Ubuntu 18.10 Cosmic. Fortunately, I am not seeing any
problematic artifacts so far. I have limited time for troubleshooting, so I
won't trouble you further. Thanks for your time*

>
> I recommend reinstalling Ubuntu and if a problem occurs with a clean
> installation then run:
>
> ubuntu-bug gdm3
>
> to create a new bug.
>
> --
> You received this bug notification because you are subscribed to the bug
> report.
> https://bugs.launchpad.net/bugs/1808125
>
> Title:
> Ubuntu 18.10 boot hangs with INTEL GRAPHICS at msg "Starting bpfilter"
>
> Status in gdm3 package in Ubuntu:
> Incomplete
>
> ---
> ProblemType: Bug
> ApportVersion: 2.20.10-0ubuntu13.1
> Architecture: amd64
> CurrentDesktop: GNOME
> DistroRelease: Ubuntu 18.10
> InstallationDate: Installed on 2018-05-07 (219 days ago)
> InstallationMedia: Ubuntu 18.04 LTS "Bionic Beaver" - Release amd64
> (20180426)
> NonfreeKernelModules: wl
> Package: gdm3 3.30.1-1ubuntu5
> PackageArchitecture: amd64
> ProcEnviron:
> TERM=xterm-256color
> PATH=(custom, no user)
> XDG_RUNTIME_DIR=<set>
> LANG=en_US.UTF-8
> SHELL=/bin/bash
> ProcVersionSignature: Ubuntu 4.18.0-12.13-generic 4.18.17
> Tags: cosmic
> Uname: Linux 4.18.0-12-generic x86_64
> UpgradeStatus: No upgrade log present (probably fresh install) [???
> UPGRADED FROM BIONIC]
> UserGroups: adm cdrom dip lpadmin plugdev sambashare sudo
> _MarkForUpload: True
> mtime.conffile..etc.gdm3.custom.conf: 2018-12-10T07:21:25.671742
>
> To manage notifications about this bug go to:
> https://bugs.launchpad.net/ubuntu/+source/gdm3/+bug/1808125/+subscriptions
>

[Daniel van Vugt (vanvugt)]

Please try the fix in comment #16.

[rtimai (rtimai)]

DANIEL!!!! DANIEL!!!!

Per your advice, I enabled the group header in 90-debian-settings, actually
a link --> sudo nano /etc/gdm3/greeter.dconf-defaults

Then I re-enabled GDM3, rebooted, and I'M BACK! I'm logging in normally
GDM3! No more SLiM!

Thank you SOO-OOOOO MUCH!

Roger

On Thu, Dec 13, 2018 at 3:00 AM Daniel van Vugt <
<email address hidden>> wrote:

> Ah, I think I see the problem. It's a syntax error in your 90-debian-
> settings. You need to also uncomment:
>
> #[org/gnome/login-screen]
>
> since it provides the context (group) information for:
>
> disable-user-list=true
>
> --
>

[rtimai (rtimai)]

How do I mark this issue *ACTUALLY* SOLVED?

I can't believe how a simple misconfiguration as a disabled group header in a configuration file could cause so much trouble. I followed instructions on some tips web site for disabling the user list in the login menu, and it *never* mentioned making sure the group header wasn't commented out.

I am so impressed that Daniel should put his finger on such an obscure cause for this catastrophic problem for me. Thanks again, Daniel.

[Daniel van Vugt (vanvugt)]

You're welcome.

In this case the correct status is 'Invalid' since it's not a bug in the default Ubuntu installation. That said, I may investigate changing the default file we install so that it's more obvious and people are less likely to make the same mistake if they want to change anything.

[rtimai (rtimai)]

Understood. You're my hero, Daniel. --Roger

On Thu, Dec 13, 2018 at 7:55 PM Daniel van Vugt <
<email address hidden>> wrote:

> You're welcome.
>
> In this case the correct status is 'Invalid' since it's not a bug in the
> default Ubuntu installation. That said, I may investigate changing the
> default file we install so that it's more obvious and people are less
> likely to make the same mistake if they want to change anything.
>
> ** Changed in: gdm3 (Ubuntu)
> Status: Incomplete => Invalid
>