• KVM (Kernel-based Virtual Machine)
• Arch Linux KVM

Hardware

Verify hardware support for virtualization:

• $ LC_ALL=C lscpu | grep Virtualization -> Virtualization: VT-x.
• $ grep -E --color=auto 'vmx|svm|0xc0f' /proc/cpuinfo -> flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx pdpe1gb rdtscp lm constant_tsc art arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc cpuid aperfmperf pni pclmulqdq dtes64 monitor ds_cpl vmx smx est tm2 ssse3 sdbg fma cx16 xtpr pdcm pcid sse4_1 sse4_2 x2apic movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand lahf_lm abm 3dnowprefetch cpuid_fault epb invpcid_single pti ssbd ibrs ibpb stibp tpr_shadow vnmi flexpriority ept vpid ept_ad fsgsbase tsc_adjust bmi1 hle avx2 smep bmi2 erms invpcid rtm mpx rdseed adx smap clflushopt intel_pt xsaveopt xsavec xgetbv1 xsaves dtherm ida arat pln pts hwp hwp_notify hwp_act_window hwp_epp md_clear flush_l1d.

Kernel

Verify kernel support for virtualization:

• $ zgrep CONFIG_KVM /proc/config.gz ->

  CONFIG_KVM_GUEST=y
  CONFIG_KVM_MMIO=y
  CONFIG_KVM_ASYNC_PF=y
  CONFIG_KVM_VFIO=y
  CONFIG_KVM_GENERIC_DIRTYLOG_READ_PROTECT=y
  CONFIG_KVM_COMPAT=y
  CONFIG_KVM=m
  CONFIG_KVM_WERROR=y
  CONFIG_KVM_INTEL=m
  CONFIG_KVM_AMD=m
  CONFIG_KVM_AMD_SEV=y
  CONFIG_KVM_MMU_AUDIT=y
  

Verify that the kernel loads modules automatically:

• $ lsmod | grep kvm ->

  kvm_intel             323584  0
  kvm                   847872  1 kvm_intel
  irqbypass              16384  1 kvm
  

Nested virtualization

• Running nested guests with KVM < KVM < Linux Virtualization Support < Docs < Linux kernel

Nested virtualization allows you to run a guest VM inside another guest VM, which becomes a "secondary host", while still using hardware acceleration from the primary host.

Verify that enabled

• $ systool -m kvm_intel -v | grep nested

Test if nested virtualization is supported by KVM:

• $ cat /sys/module/kvm_intel/parameters/nested -> Y

Enable nested virtualization permanently:

• # echo options kvm_intel nested=1 > /etc/modprobe.d/kvm_intel.conf