Tracing AMD avic svm_check_apicv_inhibit_reasons calls

zapotah

Member
Jan 25, 2015
3
0
21
Hi.

I am trying to figure out why AVIC is being disabled but my expertise ends at this juncture. I know that the avic.c library contains the function described in the topic and i suspect that is somehow traceable to see why avic is disabled. Has pve disabled avic altogether or how do i trace kvm to see why it is not passed to the qemu machines?

PVE 7.0 and "args: -global kvm-pit.lost_tick_policy=discard -cpu host,+avic,+kvm_pv_eoi,+kvm_pv_unhalt,-x2apic,-svm" passed to the qemu machine.

I run many IO intensive machines and using AVIC instead of emulated x2apic would benefit these machines immensely.
 

zapotah

Member
Jan 25, 2015
3
0
21
Basically, tracing with 'perf kvm --host --guest -a -o kvm.trace' when i start up a VM will give me a dump that contains what i believe is a call to update apicv information with kvm_request_apicv_update, but i am so far out of my depth that i have no idea how to read the rest of the output.

Any help debugging why avic is not enabled would be appreciated.
 

About

The Proxmox community has been around for many years and offers help and support for Proxmox VE, Proxmox Backup Server, and Proxmox Mail Gateway.
We think our community is one of the best thanks to people like you!

Get your subscription!

The Proxmox team works very hard to make sure you are running the best software and getting stable updates and security enhancements, as well as quick enterprise support. Tens of thousands of happy customers have a Proxmox subscription. Get your own in 60 seconds.

Buy now!