** Description changed: 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 4.15 kernel. + 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 - But 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. + 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' mount 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.
-- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1946149 Title: Bionic/linux-aws Boot failure downgrading from Bionic/linux-aws-5.4 on r5.metal To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux-aws/+bug/1946149/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
