BTW, do you know of the differences between r5.metal and r5.24xlarge? Per the specs they seem to be the same as in cpu/ram/nic/_nvme_ storage, but differ in baremetal vs nitro hypervisor?
The reason I ask is because downgrading from 5.4.0-1056-aws to 4.15.0-1113-aws worked/booted fine on r5.24xlarge, differently from r5.metal. I got to test it while looking for a similar instance type that had serial console support, but it didn't repro the problem, actually. -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux-aws in Ubuntu. https://bugs.launchpad.net/bugs/1946149 Title: Bionic/linux-aws Boot failure downgrading from Bionic/linux-aws-5.4 on r5.metal Status in linux-aws package in Ubuntu: New Bug description: When creating an r5.metal instance on AWS, the default kernel is bionic/linux-aws-5.4(5.4.0-1056-aws), when changing to bionic/linux- aws(4.15.0-1113-aws) the machine fails to boot the 4.15 kernel. If I remove these patches the instance correctly boots the 4.15 kernel https://lists.ubuntu.com/archives/kernel- team/2021-September/123963.html With that being said, after successfully updating to the 4.15 without those patches applied, I can then upgrade to a 4.15 kernel with the above patches included, and the instance will boot properly. This problem only appears on metal instances, which uses NVME instead of XVDA devices. AWS instances also use the 'discard' mount option with ext4, thought maybe there could be a race condition between ext4 discard and journal flush. Removed 'discard' from mount options and rebooted 5.4 kernel prior to 4.15 kernel installation, but still wouldn't boot after installing the 4.15 kernel. I have been unable to capture a stack trace using 'aws get-console- output'. After enabling kdump I was unable to replicate the failure. So there must be some sort of race with either ext4 and/or nvme. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux-aws/+bug/1946149/+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
