KVM vcpu0 unhandled rdmsr

virtualization
v7

(Mario Spang) #1

Nethserver 7
KVM Gast is Linux Mint

After starting the server, I see the following screen:

KVM-BUG

Why is the message displayed on the login screen. Anyway - I found a workaround on the internet. I’m not sure, should I do that?

Workaround KVM unhandled rms

Question: Is there a log file for KVM on the Nethserver?

I hope you can help me.
Best regards Mario


:flag_de: Deutscher Chat
(Mario Spang) #2

@Hunv says so:

Hi Mario,
I myself have nothing to do with KVM, but I found this post:
https://bugzilla.redhat.com/show_bug.cgi?id=874627
That sounds to me as if it were e.g. could be that the VM is emulating a newer CPU generation than the physical CPU. As a result, of course, some CPU commands are not available, but the guest tries to use.
Times so easy my first thoughts about it freely shot: slight_smile:


(Markus Neuberger) #3

Are NethServer host and Mint guest working? Then the warning may be ignored. The workaround only disables the warning.

Looks like the problem is in host linux kernel kvm code, not in qemu.
Until kvm code is fixed, this works as temporary workaround:
echo 1 >/sys/module/kvm/parameters/ignore_msrs

https://bugs.launchpad.net/qemu/+bug/1208540


(Mario Spang) #4

Yes Nethserver and Guest ist allready working.
sure the message is gone but is it fixed?

You know, if I ignore this message, the system may work with a bug. What is the result of it. Is the system still safe?

And I ask again, why is this message shown on the login screen? Before I logged in.


(Markus Neuberger) #5

I read mostly that it’s a warning to ignore but some people report about freezing systems too. Did you try to change the guest CPU as described in the link of @Hunv?

This is not an issue, see for example: https://bugs.launchpad.net/qemu/+bug/1208540

This is quite usual behaviour with kernel messages.