Background:
Ubuntu 12.04 server, running amd64 version, AMD Athlon 64 X2 5000+ CPU. KVM worked fine on the same physical hardware when previously Debian Lenny.
$ lsb_release -rd
Description: Ubuntu 12.04 LTS
Release: 12.04
$
$ apt-cache policy kvm
kvm:
Installed: 1:84+dfsg-0ubuntu16+1.0+noroms+0ubuntu13
Candidate: 1:84+dfsg-0ubuntu16+1.0+noroms+0ubuntu13
Version table:
*** 1:84+dfsg-0ubuntu16+1.0+noroms+0ubuntu13 0
500 http://gb.archive.ubuntu.com/ubuntu/ precise/main amd64 Packages
100 /var/lib/dpkg/status
$
Expected result:
KVM should start and work without error, using hardware acceleration of CPU.
Issue:
When starting a VM, I get the following message:
$ kvm -cdrom BT5R2-KDE-32.iso -m 256 -net nic -net user -vnc 127.0.0.1:2
failed to initialize KVM: Device or resource busy
Back to tcg accelerator.
And I them get the following line appear in the dmesg output:
kvm: enabling virtualization on CPU0 failed
The virtual host will still run, but with very poor performance, because it is not able to use hardware acceleration capabilities of host CPU.
My account is in the KVM group (but I get the same symptoms even running as root):
Code:
$ ls -l /dev/kvm
crw-rw---- 1 root kvm 10, 232 Jun 30 07:42 /dev/kvm
$ whoami
jason
$ grep kvm /etc/group
kvm:x:105:jason
$
The KVM kernel modules are loaded:
$ lsmod | grep kvm
kvm_amd 55848 0
kvm 415459 1 kvm_amd
$
Here is some background info on the host to hopefully help:
Code:
$ uname -a
Linux cube 3.2.0-23-generic #36-Ubuntu SMP Tue Apr 10 20:39:51 UTC 2012 x86_64 x86_64 x86_64 GNU/Linux
$ lscpu
Architecture: x86_64
CPU op-mode(s): 32-bit, 64-bit
Byte Order: Little Endian
CPU(s): 2
On-line CPU(s) list: 0,1
Thread(s) per core: 1
Core(s) per socket: 2
Socket(s): 1
NUMA node(s): 1
Vendor ID: AuthenticAMD
CPU family: 16
Model: 4
Stepping: 2
CPU MHz: 800.000
BogoMIPS: 4431.12
Virtualisation: AMD-V
L1d cache: 64K
L1i cache: 64K
L2 cache: 512K
NUMA node0 CPU(s): 0,1
$ cat /proc/cpuinfo
processor : 0
vendor_id : AuthenticAMD
cpu family : 16
model : 4
model name : AMD Athlon(tm) 5000 Dual-Core Processor
stepping : 2
microcode : 0x1000086
cpu MHz : 800.000
cache size : 512 KB
physical id : 0
siblings : 2
core id : 0
cpu cores : 2
apicid : 0
initial apicid : 0
fpu : yes
fpu_exception : yes
cpuid level : 5
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt pdpe1gb rdtscp lm 3dnowext 3dnow constant_tsc rep_good nopl nonstop_tsc extd_apicid pni monitor cx16 popcnt lahf_lm cmp_legacy svm extapic cr8_legacy abm sse4a misalignsse 3dnowprefetch osvw ibs skinit wdt npt lbrv svm_lock nrip_save
bogomips : 4431.17
TLB size : 1024 4K pages
clflush size : 64
cache_alignment : 64
address sizes : 48 bits physical, 48 bits virtual
power management: ts ttp tm stc 100mhzsteps hwpstate
processor : 1
vendor_id : AuthenticAMD
cpu family : 16
model : 4
model name : AMD Athlon(tm) 5000 Dual-Core Processor
stepping : 2
microcode : 0x1000086
cpu MHz : 800.000
cache size : 512 KB
physical id : 0
siblings : 2
core id : 1
cpu cores : 2
apicid : 1
initial apicid : 1
fpu : yes
fpu_exception : yes
cpuid level : 5
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt pdpe1gb rdtscp lm 3dnowext 3dnow constant_tsc rep_good nopl nonstop_tsc extd_apicid pni monitor cx16 popcnt lahf_lm cmp_legacy svm extapic cr8_legacy abm sse4a misalignsse 3dnowprefetch osvw ibs skinit wdt npt lbrv svm_lock nrip_save
bogomips : 4431.12
TLB size : 1024 4K pages
clflush size : 64
cache_alignment : 64
address sizes : 48 bits physical, 48 bits virtual
power management: ts ttp tm stc 100mhzsteps hwpstate
$
Do you perhaps have Virtualbox and/or VMWare installed as well?