Midclt how to add kvm config options to modprobe?

Apps and Virtualization
1

MIDCLT documentation needs to be released ASAP.
How the fuck does one add kvm report_ignored_msrs=0 option to modprobe kernel extra options?

echo “options kvm ignore_msrs=1 report_ignored_msrs=0” > /etc/modprobe.d/kvm.conf
is what i’m trying to achieve, currently attempting as a post-init script.

Seriously, this should be a very easy midclt command that NOONE SEEMS TO KNOW.

2

Suggest you

  1. describe the problem thoroughly; including hardware/software
  2. ask for assistance politely

Then someone is more likely to help.

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3

I’ve been dealing and asking about this issue since 6 months ago. Noone knows how.

The problem is simply that the usage of MIDCLT is not documented ANYWHERE. That is the issue.

The more specific issue: TrueNAS by default doesn’t set a report_ignored_msrs=0 option, in fact sets it to Y, leading to insane log spam. No post init script is able to reverse this, and if you set it via a kvm.conf file it’ll simply break on reboot.

4

Take a breath and describe the problem accurately.

There’s nothing in your description about what software you have, how many VMs , how much log spam, impact of the log spam.

Why is no-one else reporting the problem? Is there something special about your setup.

If you want smart people to spend their time, give them all the info.

5

Everyone else is reporting the problem. On proxmox or any other hypervisor that doesn’t reset all of it’s configs on reboot, it is a simple kvm modprobe option.
update-initram-fs doesn’t even work on TrueNAS due to it being read only. It’s INCREDIBLY locked down and frustratingly bad.

The issue is a simple log spam so many people after basic research give up and move on.

I have described the problem as accurately as possible. WHERE ARE THE MIDCLT DOCS? Why does it not exist?

I have already figured out a potential fix with a post init script deactivating the modules and then reactivating them after applying my parameters, and it seems to work so far.

Software: TrueNAS. Dragonfish latest RC. Any windows version that has MSR.

6

The kernel’s command-line parameters — The Linux Kernel documentation doesn’t show any option to stop ignored msrs reporting, so it may well be that such a kernel boot option doesn’t exist, but that has nothing to do with midclt.

It’s not clear if you tried it already, but have a look at setting the following paramenter in an init instead:
/sys/module/kvm/parameters/report_ignored_msrs
It defaults to Y.

Another, wholly unsupported option, is to disable the rootfs protection and make edits to the .conf.

7

It’s been a while so you propably found a solution in the meantime.
And I can feel your frustration as to find examples and docs about the midclt tool is not exactly trivial. I found out that:

  • What you are looking for is the “TrueNAS Websocket client” repo where the function and usage of the midclt tool is mentioned: GitHub - truenas/api_client
  • Where the API doc is linked here: TrueNAS Websocket Documentation. API reference can also be accessed from the TrueNAS WebUI in the top right corner: SCALE API Reference | TrueNAS Documentation Hub
  • Following the websocket documentation, I searched for “kernel” and found "kernel_advanced_options in both the system.advanced.config and system.advanced.update methods.
  • Putting 1+1 together I was able to set the values through the built-in shell:
# List advanced config and pipe to jq for readability:
midclt call system.advanced.config | jq
# List cmdline options
cat /proc/cmdline             
# Set extra kernel options:
midclt call system.advanced.update '{"kernel_extra_options":"kvm.ignore_msrs=1"}'
# Check advanced config change:
midclt call system.advanced.config | jq -r '.kernel_extra_options'
reboot now

Kernel params reference: The kernel’s command-line parameters — The Linux Kernel documentation Crucial part: “Module parameters can be specified in two ways: via the kernel command line with a module name prefix, or via modprobe.”

Hope this helps!

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