I had this same problem on a system with an "ASUS H170M-PLUS" motherboard, a Core i5-6600 CPU, internal graphics and up-to-date Ubuntu 17.10.
Booting into the recovery console worked, but when trying to boot into the desktop it would always hang somewhere before GDM becomes visible. After installing a recent UEFI firmware upgrade (to version 3606) the system booted normally again, and the kernel didn't try to load any microcode after that; based on the revision number, it seems like it contained the same microcode fix as the 'intel-microcode' (but also a ME firmware upgrade, and likely also some other necessary fixes). I wonder if the microcode fix also requires changes to the ME and/or to some UEFI functions in order to work properly? -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux 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: Confirmed Status in linux package in Ubuntu: Confirmed Status in intel-microcode source package in Xenial: Confirmed Status in linux source package in Xenial: Confirmed Status in intel-microcode source package in Artful: Confirmed Status in linux source package in Artful: Confirmed Bug description: 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 -- Mailing list: https://launchpad.net/~kernel-packages Post to : [email protected] Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
