[Bug 1904658] Re: intel-ucode sig=0x406e3 from release 3.20201110.0ubuntu0.20.04.2 hangs system in early boot

Thu Nov 19 20:13:26 UTC 2020

I have the same laptop and this is happening to me too. Sad to see this
happen again.

-- 
You received this bug notification because you are a member of Ubuntu
Foundations Bugs, which is subscribed to intel-microcode in Ubuntu.
https://bugs.launchpad.net/bugs/1904658

Title:
  intel-ucode sig=0x406e3 from release 3.20201110.0ubuntu0.20.04.2 hangs
  system in early boot

Status in intel-microcode package in Ubuntu:
  Confirmed

Bug description:
  My issue: system hang with black screen, and can try older kernels
  which present status "Loading initial ramdisk..." indefinitely.

  The symptom, issue, and the workaround are seemingly identical to
  those reported in bug#1882890, however the issue here presents with a
  different microcode update, namely 3.20201110.0ubuntu0.20.04.2.

  # reference
  * https://bugs.launchpad.net/ubuntu/+source/intel-microcode/+bug/1882890
  * https://askubuntu.com/questions/1248769/intel-microcode-3-20200609-0ubuntu0-20-04-0-update-crashes-computer-unable-to-b
  * microcode releases
  	* https://launchpad.net/ubuntu/focal/+source/intel-microcode

  # issue/error
  * boot normally gives black screen during early boot - stuck
  * boot from previous kernels also give stuck screen, but also helpfully prints "Loading initial ramdisk..." ...indefinitely.
  * boot from recovery works, can occasionally boot through to operational system from here
  * boot from recovery and running rescue commands complained of near-full /boot (96%) which was subsequently solved (removed old kernels) and initramfs rebuilt (update-initramfs -u -k all) - I thought this was the issue initially but problem remained..
  * 

  # temporary boot workaround via kernel boot option
  * can only boot successfully using dis_ucode_ldr kernel boot option:
  	* Nov 17 20:16:52 yoga710 kernel: Command line: BOOT_IMAGE=/vmlinuz-5.4.0-54-generic root=/dev/mapper/kubuntu--vg-root ro quiet splash dis_ucode_ldr

  ## kernel
  * uname -r 
  5.4.0-54-generic

  * issue appeared on 2020-11-15 on kernel 5.4.0-53
  * kernel updated today/2020-11-17 to 5.4.0-54 from 5.4.0-53 via dis_ucode_ldr booted system

  ## microcode
  microcode: sig=0x406e3 (see below)

  * sudo apt show intel-microcode 
  Package: intel-microcode
  Version: 3.20201110.0ubuntu0.20.04.2
  [...]
  APT-Manual-Installed: yes
  APT-Sources: http://ca.archive.ubuntu.com/ubuntu focal-updates/main amd64 Packages

  * dmesg | grep microcode (NOTE: this *after* a boot w boot option dis_ucode_ldr)
  [    0.038777] [Firmware Bug]: TSC_DEADLINE disabled due to Errata; please update microcode to version: 0xb2 (or later)
  [    0.125707] SRBDS: Vulnerable: No microcode
  [    0.125708] MDS: Vulnerable: Clear CPU buffers attempted, no microcode

  * dmesg | grep microcode (NOTE: this after a boot w microcode downgraded to 3.20191115.1ubuntu3)
  [    0.000000] microcode: microcode updated early to revision 0xd6, date = 2019-10-03
  [    0.131196] SRBDS: Vulnerable: No microcode
  [    0.925593] microcode: sig=0x406e3, pf=0x80, revision=0xd6
  [    0.925717] microcode: Microcode Update Driver: v2.2.

  * microcode update date via /var/log/apt/history.log:
  Start-Date: 2020-11-12  13:15:29
  Commandline: packagekit role='update-packages'
  Requested-By: **** (1000)
  Install: linux-image-5.4.0-53-generic:amd64 (5.4.0-53.59), linux-headers-5.4.0-53-generic:amd64 (5.4.0-53.59), linux-modules-extra-5.4.0-53-generic:amd64 (5.4.0-53.59), linux-headers-5.4.0-53:amd64 (5.4.0-53.59), linux-modules-5.4.0-53>
  Upgrade: libefivar1:amd64 (37-2ubuntu2, 37-2ubuntu2.1), intel-microcode:amd64 (3.20200609.0ubuntu0.20.04.2, 3.20201110.0ubuntu0.20.04.2), linux-headers-generic:amd64 (5.4.0.52.55, 5.4.0.53.56), linux-libc-dev:amd64 (5.4.0-52.57, 5.4.0->
  End-Date: 2020-11-12  13:23:05

  ## processor
  * lscpu | grep Model
  Model name:                      Intel(R) Pentium(R) CPU 4405Y @ 1.50GHz

  * iucode-tool -S
  iucode-tool: system has processor(s) with signature 0x000406e3

  ## ubuntu
  * lsb_release -rd
  Description:    Ubuntu 20.04.1 LTS
  Release:        20.04

  ## system
  * dmidecode
  System Information
          Manufacturer: LENOVO
          Product Name: 80TX
          Version: Lenovo YOGA 710-11ISK

  BIOS Information
          Vendor: LENOVO
          Version: 0UCN22WW
          Release Date: 09/27/2016
          [...]
  		BIOS Revision: 1.22
          Firmware Revision: 1.22

  # to try
  * check BIOS update status - new BIOS could fix?
  	* current: 2016-09-27
  	* available: 2018-03-26 0UCN25WW01
  		* 3. Modified: 1) Enhancement to address CVE-2017-5715.
  	* https://pcsupport.lenovo.com/us/en/products/laptops-and-netbooks/yoga-series/yoga-710-11isk/
  	* https://medium.com/@BladeCoder/flash-your-lenovo-ideapad-laptop-bios-from-linux-using-uefi-capsule-updates-a82e455ea29c

  # solution attempts
  * /boot - made space after a recovery utility complained of near-full (96%) /boot. uninstalled old kernels.

  * downgrade and hold microcode
  	* sudo apt-get install intel-microcode=3.20191115.1ubuntu3
  	* sudo apt-mark hold intel-microcode
  	* **ISSUE FIXED WITH THIS WORKAROUND**

  * reinstate current microcode to confirm
  	* sudo apt install intel-microcode=3.20201110.0ubuntu0.20.04.2
  		* "Unpacking intel-microcode (3.20201110.0ubuntu0.20.04.2) over (3.20191115.1ubuntu3)"
  		* YES - confirming the problem reappears.

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/intel-microcode/+bug/1904658/+subscriptions