Kernel 4.14 works on one VPS but not the other

xenogamers · n00b Joined: 02 Aug 2017 Posts: 5

So the VPS is running on kernel 4.12, and doing an upgrade of that config to 4.14, the VPS won't boot and shows this:
https://i.gyazo.com/f806f1031f02aa77ec2dd7ec78c51970.png

However, with that same config, it boots just fine on another VPS with the same hypervisor type.

I'm not sure how to debug, and has anyone experienced anything similar to this?

Thanks!

blopsalot · Apprentice Joined: 28 Jan 2017 Posts: 231

if they were truly the same, you wouldn't be having this issue, you need to figure out what's different with the hosts. if you have no control/access to the hosts, you can either start debugging or I would look at gcc plugins and other security options first.

https://wiki.gentoo.org/wiki/Kernel_Crash_Dumps

ct85711 · Veteran Joined: 27 Sep 2005 Posts: 1791

From the output you posted, didn't really give a error message that is significant. The most it said, is that it detected some devices found but not in the kernel. So more likely if there was a more significant error, it was later and not shown. Otherwise a common cause for the startup seem to hang for a while, is that it is attempting to find and load some firmware but unable to find them. Assuming you are using an initrd, I'd check that to make sure it contains the necessary firmware.

xenogamers · n00b Joined: 02 Aug 2017 Posts: 5

It's odd but I found the issue.

For all the VPSes I set the /etc/default/grub to set the IO scheduler to BFQ:
GRUB_CMDLINE_LINUX_DEFAULT="elevator=bfg numa=off"

And the first one has no issues with this, but I guess commenting out that line in the other two VPSes causes it to boot just fine.

I've just made a script in /etc/local.d to set the IO scheduler from now on.