Arch Linux

Amunak

Member

From: Czech Republic

Registered: 2010-08-21

Posts: 15

kernel error on QEMU VM boot: Failed to access perfctr msr

I've been encountering this error on boot:

Apr 12 15:03:48 AMU-SERVER kernel: smpboot: CPU0: Intel QEMU Virtual CPU version (cpu64-rhel6) (fam: 06, model: 0d, stepping: 03)
Apr 12 15:03:48 AMU-SERVER kernel: Performance Events: Broken PMU hardware detected, using software events only.
Apr 12 15:03:48 AMU-SERVER kernel: Failed to access perfctr msr (MSR c1 is 0)
Apr 12 15:03:48 AMU-SERVER kernel: Brought up 1 CPUs
Apr 12 15:03:48 AMU-SERVER kernel: smpboot: Total of 1 processors activated (3601.99 BogoMIPS)
Apr 12 15:03:48 AMU-SERVER kernel: NMI watchdog: disabled (cpu0): hardware events not enabled

The system works well for months, but still - I'd like to know what's causing this error and how to get rid of it.

Thanks.

thoth

Member

Registered: 2010-01-10

Posts: 79

Re: kernel error on QEMU VM boot: Failed to access perfctr msr

+1 found this on a KVM install

falconindy

Developer

From: New York, USA

Registered: 2009-10-22

Posts: 4,111

Website

Re: kernel error on QEMU VM boot: Failed to access perfctr msr

No problems here... the command line you're using to start the VM seems quite relevant here.

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blog | ±github

thoth

Member

Registered: 2010-01-10

Posts: 79

Re: kernel error on QEMU VM boot: Failed to access perfctr msr

just using virt-manager here with all default settings nothing special, anything you'd recommend?

mich41

Member

Registered: 2012-06-22

Posts: 796

Re: kernel error on QEMU VM boot: Failed to access perfctr msr

I'd like to know what's causing this error

It's not an error, it says that the CPU doesn't support performance counters.

AFAIK Linux doesn't use them for anything but NMI watchdog and if you aren't going to do PMU-based software profiling on the guest system you don't need them too.

and how to get rid of it.

It seems that some people tried to implement PMU in qemu-kvm; I'd start here. Or just ignore it.

BTW, if you don't need PMU but still want some watchdog, QEMU can emulate one.

Last edited by mich41 (2013-05-28 20:16:58)

thoth

Member

Registered: 2010-01-10

Posts: 79

Re: kernel error on QEMU VM boot: Failed to access perfctr msr

I wish I could ignore it, but unfortunately this install sits dead in the water immediately after grub with this error:

'Failed to access perfctr msr'

mich41

Member

Registered: 2012-06-22

Posts: 796

Re: kernel error on QEMU VM boot: Failed to access perfctr msr

Probably something unrelated, maybe booting without "quiet" would reveal what exactly is happening before it hangs.

endle

Member

Registered: 2013-07-07

Posts: 1

Re: kernel error on QEMU VM boot: Failed to access perfctr msr

Probably something unrelated, maybe booting without "quiet" would reveal what exactly is happening before it hangs.

Thank you! After booting without 'quiet', I found where the problem is.