Well, I *think* I can answer my own question about the signed image. The signed image was *not* generated by my installing the lp1759920 kernel. In fact it is the identical file to the one from: https://launchpad.net/ubuntu/+archive/primary/+files/kernel-signed-image-4.13.0-38-generic-di_4.13.0-38.43_amd64.udeb (which is a link from https://launchpad.net/ubuntu/+source/linux-signed).
Given that no similar package is installed on my system for *any* signed kernel image I'm at a loss to know how and when they *do* get signed. But this does explain why my laptop still hangs - it's because it isn't actually running the lp1759920 kernel. Is there any (simple-ish) way to generate a signed image from the unsigned one? -- 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 : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp