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linux-kernelvirtualizationkvm

Why do we still need QEMU while KVM is also a hypervisor?

I have known that KVM is a module of Linux Kernel, KVM converts Linux into a type-1 (bare-metal) hypervisor. Show why we need QEMU to work with KVM? Is these any feature that QEMU has but KVM doesn't?

Solution

  • What is the difference between KVM and QEMU?

    QEMU uses emulation; KVM uses processor extensions (HVM) for virtualization.

    http://www.linux-kvm.org/page/FAQ#General_KVM_information

    My understanding of the above for example, is that QEMU can emulate ARM on an x64 based system because its full emulation. KVM uses CPU extensions so is limited to running the same base system as the physical CPU.

    "Unlike native QEMU, which uses emulation, KVM is a special operating mode of QEMU that uses CPU extensions (HVM) for virtualization via a kernel module. ", So No you would need to have Qemu installed to run VM's. --> wiki.archlinux.org/index.php/KVM