I recompiled the 4.18.0-20-general kernel and made the following changes, and things start to work.
258c258,261 < --- > if (limit < 1) { > pr_err("efi: Invalid name size %ld/%d.\n", name_size, limit); > return 0; > } Logs proving the fix worked: [ 0.321692] Registered efivars operations [ 0.330723] efi: efi: Invalid name size 0/0. -- 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/1830951 Title: kernel panic: stack corrupted in efivar_ssdt_iter+0xd3/0xe8 Status in linux package in Ubuntu: Confirmed Bug description: We have a few 2010 mac pro running 1604 LTS that are just upgraded to Ubuntu 1804 LTS. While they all worked fine with the 1604 LTS and 4.4 kernel, they can no longer boot with the 4.15.0-50 kernel installed with 1804. We tried various kernel flags without luck, and installed latest 4.18.0-20 from HWE and got the same result. Unfortunately, no logs are created in /var/logs when the issue happens, and we could only boot with the old 4.4 kernel. We had to enable earlyprintk=efi to get a backtrace in a photo. The issue happens consistently, i.e. the backtrace looks always the same just happens on different cores. Attached the boot-info output and the picture taken at the end of the kernel loading. --- ProblemType: Bug ApportVersion: 2.20.9-0ubuntu7.6 Architecture: amd64 AudioDevicesInUse: USER PID ACCESS COMMAND /dev/snd/controlC2: steventang 2047 F.... pulseaudio /dev/snd/controlC0: steventang 2047 F.... pulseaudio /dev/snd/controlC1: steventang 2047 F.... pulseaudio CurrentDesktop: ubuntu:GNOME DistroRelease: Ubuntu 18.04 HibernationDevice: RESUME=UUID=a7ceb7f0-6040-4236-ad7d-35780a1dc870 InstallationDate: Installed on 2019-05-28 (0 days ago) InstallationMedia: Ubuntu 16.04 LTS "Xenial Xerus" - Release amd64 (20160420.1) MachineType: Apple Inc. MacPro5,1 NonfreeKernelModules: wl Package: linux (not installed) ProcFB: 0 radeondrmfb ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.4.0-148-generic root=UUID=8d18bfd8-303b-4397-9216-a0e48cb6ef54 ro quiet splash ProcVersionSignature: Ubuntu 4.4.0-148.174-generic 4.4.177 RelatedPackageVersions: linux-restricted-modules-4.4.0-148-generic N/A linux-backports-modules-4.4.0-148-generic N/A linux-firmware 1.173.6 Tags: bionic Uname: Linux 4.4.0-148-generic x86_64 UpgradeStatus: No upgrade log present (probably fresh install) UserGroups: adm cdrom dip lpadmin plugdev sambashare sudo _MarkForUpload: True dmi.bios.date: 08/08/17 dmi.bios.vendor: Apple Inc. dmi.bios.version: MP51.88Z.0084.B00.1708080528 dmi.board.asset.tag: 0 dmi.board.name: Mac-F221BEC8 dmi.board.vendor: Apple Inc. dmi.chassis.type: 7 dmi.chassis.vendor: Apple Inc. dmi.chassis.version: Mac-F221BEC8 dmi.modalias: dmi:bvnAppleInc.:bvrMP51.88Z.0084.B00.1708080528:bd08/08/17:svnAppleInc.:pnMacPro5,1:pvr0.0:rvnAppleInc.:rnMac-F221BEC8:rvr:cvnAppleInc.:ct7:cvrMac-F221BEC8: dmi.product.name: MacPro5,1 dmi.product.version: 0.0 dmi.sys.vendor: Apple Inc. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1830951/+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