Ubuntu 16.04 with kernel 4.4.0-148 hangs on boot on a ThinkPad L460 while 4.4.0-145 doesnt

[Max Pfaffinger]

After the automatic update from 4.4.0-145 to 4.4.0-148 on a Thinkpad L460 the boot process hangs before any visible output and doesnt proceed from there.

Changing back to 4.4.0-145 in the grub menu makes the boot proceed normally.

> lspci -knn | grep -A3 VGA

00:02.0 VGA compatible controller [0300]: Intel Corporation Skylake GT2 [HD Graphics 520] [8086:1916] (rev 07)
        Subsystem: Lenovo Skylake Integrated Graphics [17aa:5051]
        Kernel driver in use: i915_bpo
        Kernel modules: i915_bpo

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: linux-image-4.4.0-145-generic 4.4.0-145.171
ProcVersionSignature: Ubuntu 4.4.0-145.171-generic 4.4.176
Uname: Linux 4.4.0-145-generic x86_64
ApportVersion: 2.20.1-0ubuntu2.18
Architecture: amd64
CurrentDesktop: Unity
Date: Sun May 19 16:36:06 2019
InstallationDate: Installed on 2016-11-04 (925 days ago)
InstallationMedia: Ubuntu 16.04.1 LTS "Xenial Xerus" - Release amd64 (20160719)
SourcePackage: linux-signed
UpgradeStatus: No upgrade log present (probably fresh install)

[Max Pfaffinger (galabrul3)]

Whan starting 4.4.0-148 in recovery mode, this is the position where the system hangs.

[sarat bhaswanth (sarat.bhaswanth)]

Any update? Same problem here

[Diederik (j-h-j-houtkoop)]

I have almost the same problem.
i run ubuntu 14.04 and for me its linux 4.4.0-146 that starts normal

148 only give the purple ubutu screen, but nothing after that
148 recovery stops after initial RAM disk

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Krzysztof Ślazyk (krzysztof-slazyk)]

The same on Lenovo desktop, had to downgrade to 4.4.0-146.
Kernel driver in use: i915

[Tom Reynolds (tomreyn)]

Diederik: Ubuntu 14.04 reached end of life, is no longer supported.

Max, and anyone else affected by this issue with identical symptoms as Max on Ubuntu 16.04 with kernel 4.4.0-148, please consider testing this:

1. Add this to /etc/default/grub :
GRUB_GFXPAYLOAD_LINUX="text"

2. Add this to the GRUB_CMDLINE_LINUX_DEFAULT option in /etc/default/grub :
earlyprintk=efi,keep

3. Run: sudo update-grub

4. Try all of the following combinations of kernel boot parameters by editing them at the grub menu (https://wiki.ubuntu.com/Kernel/KernelBootParameters):
  mitigations=off
  dis_ucode_ldr mitigations=off
  dis_ucode_ldr mds=off
(Only) if any of these combinations boot fine, try them again at least five times or until a boot fails. Take notes and finally report how often you tried them and how often they booted fine, and whether there was a failed boot for each of these combinations.

[RB (erpuntbakker)]

Same issue here, Thinkpad L460, Lubuntu 16.04, affected kernels 4.4.0-148 and 4.4.0-150, same screenshot as Max P.
Booting kernel -146 works fine.

[RB (erpuntbakker)]

@Tom Reynolds,

when I use dis_ucode_ldr as a kernel boot parameter, booting and shutdown work fine.
Whether or not I also add mitigations=off or mds=off does not matter.
Tested five times with 4.4.0-154.

The older kernel 4.4.0-146 boots fine without special parameters, but hangs on shutdown.

[Miha Peta (mcshell)]

I had same problem on ThinkPad 13 with Kubuntu 16.04.

Adding dis_ucode_ldr as a kernel boot parameter solved the problem.

Thank you!