Hi everyone, Keith, thanks for testing! It is fantastic news that the test kernel fixes the issue, and our theory is correct, and we are on the right track.
I also tested both test kernels myself, and can confirm that reverting "randomize_kstack: Improve entropy diffusion" fixes the issue, and that "randomize_kstack: Remove non-functional per-arch entropy filtering" has no improvement at all, and still has the issue. So, I think the way forward is to do the unpopular thing, which is to revert "randomize_kstack: Improve entropy diffusion". We should never have changed something so fundamental as the kernel thread stack size on a stable kernel. We can do that on the development release sure, but not on LTS kernels. I will have a talk with the Kernel team about it, but I will begin preparing the patches and writing a SRU template. Thanks, Matthew -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux-signed-hwe-5.15 in Ubuntu. https://bugs.launchpad.net/bugs/2073267 Title: Virtualbox Guru meditation on VM start caused by kernel commit in v6.9-rc4 Status in linux package in Ubuntu: Triaged Status in linux-signed-hwe-5.15 package in Ubuntu: Confirmed Status in virtualbox package in Ubuntu: Confirmed Bug description: It worked yesterday, but today I get a Guru Meditation trying to start some of my virtual machines. This shows up in VBox.log as "VCPU0: Guru Meditation -2708 (VERR_VMM_SET_JMP_ABORTED_RESUME)". I suspect this may have started due to a Linux kernel upgrade I installed this morning. A fresh VM with no disk shows the issue. Sometimes turning off the I/O APIC makes the issue go away, sometimes not. Turning off nested paging sometimes lets VirtualBox make a little bit of progress w.r.t. booting VMs, but that usually still crashes before the VM finishes starting. This may be related to this bug reported on the VirtualBox forums: https://forums.virtualbox.org/viewtopic.php?t=111889&sid=5cd33c0872a03b689e7e9f84d850f538 https://forums.virtualbox.org/viewtopic.php?t=111918 Ubuntu is 22.04.4 LTS, kernel is 5.15.0-116-generic, VirtualBox is 6.1.50-dfsg-1~ubuntu1.22.04.1. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2073267/+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
