How do we check core temps in qubes?

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1

On windows pc’s, I always run Core Temp (url) to monitor cpu temps.

Is there an equivalent for qubes, and where do I run it, from dom0 I assume.

Thanks

2

sensors in dom0, but you probably can’t see the core temp.

I think on most CPU you need access to the physical core to read the temp, and dom0 can only see the xen vcpu.

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3

sensors can’t be accurate, says gpu 0 C and cpu 25 C which sounds too low for a laptop, but no way to really tell

I’ll search for xen tools, must be one somewhere, was hoping for a quick n easy answer here though

4

Redacted, as what I stated was incorrect.

What i think remains valid, is that the dom0/admin-vm relies on the underlying virtualization layer (xen hypervisor) to provide information about the host hardware, such as temperature sensors .

Initial (incorrect) text **TL;DR**: fetching hypervisor its hardware-sensors their temperature-outputs seems to be "impossible".

A tool for a qube/VM (for instance “dom0”) to retrieve information about its hypervisor, is xl info .
Temperatures are not listed in that overview.
It seems that the tool uses hypercalls to query the hypervisor for information.
A quick search for a hypercall returning (values of) hardware-sensors / temperatures did not provide any results.

5

I’m surprised to read that because sensors on my desktop reports very accurate temps and voltage for all the components, I even use xfce widget for sensors and the values are similar to what I have on Linux

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6

I can read all data except the temperature of each CPU core, the external CPU temp GPU temp etc. works just fine, same with all fan speeds, voltages etc.

The only difference I can see between xen and bare metal is the core temperature.

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7

You can access the hardware monitoring chip that is present on motherboard but you can’t access CPU directly from dom0 and there is currently no Xen support for providing access to this CPU information to guests:

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8

Thanks all

I guess I should qualify this is a fresh qubes 4.1.2 (r4.1) install on new novacustom nv41 laptop. I have not upgraded to testing yet.

I did some poking around, and searching for xen info, found this so far:

NovaCustom NV41 laptop:

Qubes OS release 4.1.2 (R4.1)
xen_version: 4.14.6
Linux 6.5.8-1.qubes.fc32.x86_64

dmidecode is installed by default in dom0 good!

sensors only reports one core, is it average? or first? highest? no clue

cat /proc/loadavg
cat /proc/cpuinfo

hddtemp /dev/nvme0n1p1

sensors-detect

xl info

Like others have mentioned, pretty much all hardware EXCEPT cpu core temperatures are identifiable from dom0. Haven’t hit the xen mailing list yet, but so far, nothing on their wiki on this.

Starting to look like xen doesn’t pass core temp to vm’s, which makes me wonder how do they manage xen servers. Thinking about installing basic xen project (url) on a test pc, to get a better feel for it, kind of curious at this point.

9

Thanks for that link, I already started with some of it (sensors-detect) will look into further. Already locked up my laptop once, so likely build a test pc today. Since I’m currently running the stable 4.1.2 version of qubes, which is xen 4.14.6, the patch from that thread might still work, but kind of pointless if latest qubes testing 4.2r5 uses a newer version of xen (haven’t checked yet).

xen devs really need to add this feature, it’s a shame they resist, people clearly want the functionality.

10

Noticed a few things in ‘xl dmesg’

[user@dom0 ~]$ xl dmesg
(XEN) Unrecognised CPU model 0x9a - assuming vulnerable to LazyFPU
(XEN) CPU2: Temperature above threshold
(XEN) CPU2: Running in modulated clock mode

doh! really irks me, want those core temps

sensors always reports cpu 25.0C never changes, that can’t be right. fan speeds do change, that’s good.

Tempted to upgrade to qubes 4.2rc5 at this point, and work from there.