[Bug 1759920] Re: intel-microcode 3.20180312.0 causes lockup at login screen(w/ linux-image-4.13.0-37-generic)

[Michael Mauch]

Thank you, Tyler, your 4.4 kernel has been working great for half a day,
even with the DVB-related patches for my DVB card.

viscacha% cat /proc/version_signature
Ubuntu 4.4.0-119.143+lp1759920.1-generic 4.4.114
viscacha% cat /proc/cmdline
BOOT_IMAGE=/boot/vmlinuz-4.4.0-119-generic root=UUID=009b027c-db85-4cd1-909a-a658aaab5394 ro nodmraid enable_mtrr_cleanup quiet splash ignore_loglevel i8042.noaux=1 video=vesafb:off intel_idle.max_cstate=1 console=ttyS0,115200 vt.handoff=7
viscacha% dmesg -t | grep -i microcode
microcode: CPU0 microcode updated early to revision 0x2d, date = 2018-02-07
microcode: CPU1 microcode updated early to revision 0x2d, date = 2018-02-07
microcode: CPU2 microcode updated early to revision 0x2d, date = 2018-02-07
microcode: CPU3 microcode updated early to revision 0x2d, date = 2018-02-07
microcode: CPU0 sig=0x206a7, pf=0x2, revision=0x2d
microcode: CPU1 sig=0x206a7, pf=0x2, revision=0x2d
microcode: CPU2 sig=0x206a7, pf=0x2, revision=0x2d
microcode: CPU3 sig=0x206a7, pf=0x2, revision=0x2d
microcode: CPU4 sig=0x206a7, pf=0x2, revision=0x2d
microcode: CPU5 sig=0x206a7, pf=0x2, revision=0x2d
microcode: CPU6 sig=0x206a7, pf=0x2, revision=0x2d
microcode: CPU7 sig=0x206a7, pf=0x2, revision=0x2d
microcode: Microcode Update Driver: v2.01 <tigran at aivazian.fsnet.co.uk>, Peter Oruba

-- 
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/1759920

Title:
  intel-microcode 3.20180312.0 causes lockup at login screen(w/ linux-
  image-4.13.0-37-generic)

Status in intel-microcode package in Ubuntu:
  Invalid
Status in linux package in Ubuntu:
  Invalid
Status in intel-microcode source package in Trusty:
  Invalid
Status in linux source package in Trusty:
  Fix Committed
Status in intel-microcode source package in Xenial:
  Invalid
Status in linux source package in Xenial:
  Fix Committed
Status in intel-microcode source package in Artful:
  Invalid
Status in linux source package in Artful:
  Fix Committed

Bug description:
  [Impact]

   * Some systems experience kernel lockups after updating to the latest intel-microcode
     package or when receiving updated microcode from a BIOS update.

   * In many cases, the lockups occur before users can reach the login screen which makes
     it very difficult to debug/workaround.

  [Test Case]

   * The most reliable test case currently known is to install the sssd package. Lockups
     may occur during package installation (disable IBPB by writing 0 to
     /proc/sys/kernel/ibpb_enabled to prevent this from happening). A lockup will most
     likely occur just after booting the system up as the lock screen is displayed.

  [Regression Potential]

   * The fix is in the task switching code of the kernel so complexity of the change is
     relatively high.

  [Original Report]

  I don't know if this is a problem with the kernel or the microcode,
  but we have a significant number of computers in our organization (on
  both 16.04 and 17.10) that fail if they have both updated.  Booting
  with either linux-image-4.13.0-36-generic or intel-microcode
  3.20180108.0+really20170707ubuntu17.10.1 allows all these computers to
  boot.

  ## Workaround ##
  1. Boot the system with the dis_ucode_ldr kernel boot parameter to temporary avoid the problem:
     https://wiki.ubuntu.com/Kernel/KernelBootParameters
  2. Install the previous version of package from
     https://launchpad.net/~ubuntu-security-proposed/+archive/ubuntu/ppa/+build/14261530/+files/intel-microcode_3.20180108.0+really20170707ubuntu16.04.1_amd64.deb
  3. (Optional) Hold the package so that it won't be upgraded accidentally
     sudo apt-mark hold intel-microcode

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/intel-microcode/+bug/1759920/+subscriptions