KVM module access lost after upgrade from v5.0beta to v5.0?

[elimus_]

I am encountering an interesting problem. I was upgrading my homelab proxmox installation from 5.0-5/c155b5bc build to 5.0-30 build. And now after upgrade I encounter issue that I can no longer run VMs as system thinks that KVM is not accessible.

...
root@pve:~# qm start 101
Could not access KVM kernel module: No such file or directory
failed to initialize KVM: No such file or directory
start failed: command '/usr/bin/kvm -id 101 -chardev 'socket,id=qmp,path=/var/run/qemu-server/101.qmp,server,nowait' -mon 'chardev=qmp,mode=control' -pidfile /var/run/qemu-server/101.pid -daemonize -smbios 'type=1,uuid=4142b375-4554-4ac4-a3f8-d153e0d6a4f2' -name CHR-TheDude -smp '3,sockets=1,cores=3,maxcpus=3' -nodefaults -boot 'menu=on,strict=on,reboot-timeout=1000,splash=/usr/share/qemu-server/bootsplash.jpg' -vga std -vnc unix:/var/run/qemu-server/101.vnc,x509,password -cpu kvm64,+lahf_lm,+sep,+kvm_pv_unhalt,+kvm_pv_eoi,enforce -m 512 -k en-us -device 'pci-bridge,id=pci.1,chassis_nr=1,bus=pci.0,addr=0x1e' -device 'pci-bridge,id=pci.2,chassis_nr=2,bus=pci.0,addr=0x1f' -device 'piix3-usb-uhci,id=uhci,bus=pci.0,addr=0x1.0x2' -device 'usb-tablet,id=tablet,bus=uhci.0,port=1' -device 'virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x3' -iscsi 'initiator-name=iqn.1993-08.org.debian:01:8fcb8aa68fb5' -drive 'file=/mnt/ssd120/images/101/vm-101-disk-1.raw,if=none,id=drive-virtio0,format=raw,cache=none,aio=native,detect-zeroes=on' -device 'virtio-blk-pci,drive=drive-virtio0,id=virtio0,bus=pci.0,addr=0xa,bootindex=100' -device 'ahci,id=ahci0,multifunction=on,bus=pci.0,addr=0x7' -drive 'file=/mnt/ssd120/images/101/vm-101-disk-2.qcow2,if=none,id=drive-sata1,format=qcow2,cache=none,aio=native,detect-zeroes=on' -device 'ide-drive,bus=ahci0.1,drive=drive-sata1,id=sata1' -netdev 'type=tap,id=net0,ifname=tap101i0,script=/var/lib/qemu-server/pve-bridge,downscript=/var/lib/qemu-server/pve-bridgedown,vhost=on' -device 'virtio-net-pci,mac=4E:07:F6:39:60:EC,netdev=net0,bus=pci.0,addr=0x12,id=net0,bootindex=300'' failed: exit code 1
...

I am running cheaper FX8300 system, and I am sure that virtualization is enabled in bios. Double checked as a matter of fact to make sure that bios haven't been reset by some reason.

So far I have not managed to find any solutions to this. Has anyone encountered anything similar with AMD systems?

What I've tried:
* Disabling/Enabling virtualization in bios.
* Loading kvm-amd with modprobe
...
root@pve:~# modprobe kvm-amd
modprobe: ERROR: could not insert 'kvm_amd': Invalid argument
...
* Rechecking if SVM cpu flag is seen by system: it is.

 

[t.lamprecht]

I am encountering an interesting problem. I was upgrading my homelab proxmox installation from 5.0-5/c155b5bc build to 5.0-30 build. And now after upgrade I encounter issue that I can no longer run VMs as system thinks that KVM is not accessible.

Can you try an older kernel? Just select an older one in grub by going to the "Advanced .." menu if you have not manually removed older versions.

Also try:

#first
modprobe kvm
modprobe kvm-amd

# whats output of this:
modinfo kvm-amd

 

[elimus_]

Thank you for reply.

Thanks to your suggestion to try older kernel version I actually noticed what I had done wrong... I used to run this on Intel machine and I had changed to AMD hardware with the same system disk. The problem was that I had left nested configuration that works for kvm-intel module.

error:
[ .. ] kvm_amd: 'Y' invalid parameter 'nested'
modprobe: error: could not insert 'kvm_amd': invalid argument

After I re-applied amd config: "echo "options kvm-amd nested=1" > /etc/modprobe.d/kvm-amd.conf" I could once again load kvm-amd with modprobe.

TLDR, dumb mistake for nested config in kvm module, AMD needs 1 instead of Y for intel.

 

[t.lamprecht]

I used to run this on Intel machine and I had changed to AMD hardware with the same system disk. The problem was that I had left nested configuration that works for kvm-intel module.

Uh, ok, that's an evil one... Glad you figured it out yourself!