Description:
I am experiencing an issue with obtaining detailed CPU information using the dmidecode command on a Linux guest OS virtual machine running in VirtualBox. The dmidecode command provides only limited data, while other commands like lscpu and cat /proc/cpuinfo return complete CPU details.
Steps to Reproduce:
- Install Debian11/12 or Ubuntu22.04 as a guest OS in VirtualBox.
- Run the
sudo dmidecodecommand to obtain hardware information.
Expected Results:
The dmidecode command should provide detailed CPU information similar to what is provided by lscpu and /proc/cpuinfo.
Actual Results:
The dmidecode command returns limited information, mostly related to the BIOS and basic system configuration. Detailed CPU information is not included.
Example Output:
Here is the output of the sudo dmidecode command on my Debian12 VM:
# dmidecode 3.4
Getting SMBIOS data from sysfs.
SMBIOS 2.5 present.
10 structures occupying 450 bytes.
Table at 0x000E1000.
Handle 0x0000, DMI type 0, 20 bytes
BIOS Information
Vendor: innotek GmbH
Version: VirtualBox
Release Date: 12/01/2006
Address: 0xE0000
Runtime Size: 128 kB
ROM Size: 128 kB
Characteristics:
ISA is supported
PCI is supported
Boot from CD is supported
Selectable boot is supported
8042 keyboard services are supported (int 9h)
CGA/mono video services are supported (int 10h)
ACPI is supported
Handle 0x0001, DMI type 1, 27 bytes
System Information
Manufacturer: innotek GmbH
Product Name: VirtualBox
Version: 1.2
Serial Number: 0
UUID: e83f6988-828d-5142-a0e2-2bca4c199fc3
Wake-up Type: Power Switch
SKU Number: Not Specified
Family: Virtual Machine
Handle 0x0008, DMI type 2, 15 bytes
Base Board Information
Manufacturer: Oracle Corporation
Product Name: VirtualBox
Version: 1.2
Serial Number: 0
Asset Tag: Not Specified
Features:
Board is a hosting board
Location In Chassis: Not Specified
Chassis Handle: 0x0003
Type: Motherboard
Contained Object Handles: 0
Handle 0x0003, DMI type 3, 13 bytes
Chassis Information
Manufacturer: Oracle Corporation
Type: Other
Lock: Not Present
Version: Not Specified
Serial Number: Not Specified
Asset Tag: Not Specified
Boot-up State: Safe
Power Supply State: Safe
Thermal State: Safe
Security Status: None
Handle 0x0007, DMI type 126, 42 bytes
Inactive
Handle 0x0005, DMI type 126, 15 bytes
Inactive
Handle 0x0006, DMI type 126, 28 bytes
Inactive
Handle 0x0002, DMI type 11, 7 bytes
OEM Strings
String 1: vboxVer_6.1.50
String 2: vboxRev_161033
Handle 0x0004, DMI type 128, 8 bytes
OEM-specific Type
Header and Data:
80 08 04 00 FF C5 2A 00
Handle 0xFEFF, DMI type 127, 4 bytes
End Of Table
Commands That Work: The following commands provide complete CPU details:
lscpucat /proc/cpuinfo
Example lscpu Output:
root@faiserver:~# lscpu
Architecture: x86_64
CPU op-mode(s): 32-bit, 64-bit
Address sizes: 39 bits physical, 48 bits virtual
Byte Order: Little Endian
CPU(s): 1
On-line CPU(s) list: 0
Vendor ID: GenuineIntel
Model name: 11th Gen Intel(R) Core(TM) i7-1165G7 @ 2.80GHz
BIOS Model name: CPU @ 0.0GHz
BIOS CPU family: 0
CPU family: 6
Model: 140
Thread(s) per core: 1
Core(s) per socket: 1
Socket(s): 1
Stepping: 1
BogoMIPS: 5606.39
Flags: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse ss
e2 ht syscall nx rdtscp lm constant_tsc rep_good nopl xtopology nonstop_tsc cpuid tsc_known_fre
q pni pclmulqdq monitor ssse3 cx16 pcid sse4_1 sse4_2 x2apic movbe popcnt aes xsave avx rdrand
hypervisor lahf_lm abm 3dnowprefetch invpcid_single pti fsgsbase avx2 invpcid rdseed clflushopt
md_clear flush_l1d arch_capabilities
Virtualization features:
Hypervisor vendor: KVM
Virtualization type: full
Caches (sum of all):
L1d: 48 KiB (1 instance)
L1i: 32 KiB (1 instance)
L2: 1.3 MiB (1 instance)
L3: 12 MiB (1 instance)
NUMA:
NUMA node(s): 1
NUMA node0 CPU(s): 0
Vulnerabilities:
Gather data sampling: Unknown: Dependent on hypervisor status
Itlb multihit: KVM: Mitigation: VMX unsupported
L1tf: Mitigation; PTE Inversion
Mds: Mitigation; Clear CPU buffers; SMT Host state unknown
Meltdown: Mitigation; PTI
Mmio stale data: Not affected
Retbleed: Not affected
Spec rstack overflow: Not affected
Spec store bypass: Vulnerable
Spectre v1: Mitigation; usercopy/swapgs barriers and __user pointer sanitization
Spectre v2: Mitigation; Retpolines, STIBP disabled, RSB filling, PBRSB-eIBRS Not affected
Srbds: Not affected
Tsx async abort: Not affected
root@faiserver:~#
Example /proc/cpuinfo Output:
root@faiserver:~# cat /proc/cpuinfo
processor : 0
vendor_id : GenuineIntel
cpu family : 6
model : 140
model name : 11th Gen Intel(R) Core(TM) i7-1165G7 @ 2.80GHz
stepping : 1
cpu MHz : 2803.198
cache size : 12288 KB
physical id : 0
siblings : 1
core id : 0
cpu cores : 1
apicid : 0
initial apicid : 0
fpu : yes
fpu_exception : yes
cpuid level : 22
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 rdtscp lm constant_tsc rep_good nopl xtopology nonstop_tsc cpuid tsc_known_freq pni pclmulqdq monitor ssse3 cx16 pcid sse4_1 sse4_2 x2apic movbe popcnt aes xsave avx rdrand hypervisor lahf_lm abm 3dnowprefetch invpcid_single pti fsgsbase avx2 invpcid rdseed clflushopt md_clear flush_l1d arch_capabilities
bugs : cpu_meltdown spectre_v1 spectre_v2 spec_store_bypass l1tf mds swapgs itlb_multihit gds
bogomips : 5606.39
clflush size : 64
cache_alignment : 64
address sizes : 39 bits physical, 48 bits virtual
power management:
root@faiserver:~#
Request for Assistance:
- Is there a way to configure VirtualBox to expose more detailed SMBIOS information to the guest OS?
- Are there any settings or additional steps that can be taken to enable
dmidecodeto retrieve full CPU information in a VirtualBox VM? - Any insights or suggestions to address this issue would be greatly appreciated.
Thank you for your assistance.
