KVM – kernel-based virtualization for Linux

KVM (Kernel-based Virtual Machine) is the virtualization infrastructure integrated into the Linux kernel. It allows Linux to function as a hypervisor, running multiple isolated virtual machines that can each execute their own operating system.

KVM uses processor virtualization extensions to execute guest instructions efficiently. The kernel provides virtual CPU execution, memory management and access to hardware-assisted virtualization facilities, while user-space applications supply the surrounding virtual machine environment.

QEMU is commonly used alongside KVM to provide virtual hardware, including storage controllers, network interfaces and display devices. KVM itself does not provide a complete graphical management interface. Instead, administrators can use QEMU directly or management tools such as libvirt, virt-manager and higher-level virtualization platforms.

KVM supports several processor architectures beyond x86, including Arm, IBM Z and PowerPC, subject to hardware and kernel support. Its integration into Linux makes it suitable for desktop virtualization, development environments, private clouds and large-scale server infrastructure.

This is free and open source software.

Key Features

• Hardware-assisted virtualization integrated directly into the Linux kernel.
• Run multiple isolated virtual machines simultaneously.
• Support Linux, Windows and other compatible guest operating systems.
• Use processor virtualization extensions including Intel VT-x and AMD-V.
• Support virtualization on x86, Arm, IBM Z and other supported architectures.
• Provide virtual CPU execution and guest memory management.
• Integrate with QEMU for device emulation and complete virtual machine environments.
• Support virtio paravirtualized network, storage and other devices.
• Kernel Samepage Merging (KSM) to reduce memory consumption where applicable.
• Memory ballooning and huge-page support for virtual machine workloads.
• CPU and memory hotplug capabilities for supported guests.
• PCI and GPU passthrough through VFIO and IOMMU facilities.
• Support nested virtualization on compatible hardware and kernels.
• Virtual machine snapshots, state preservation and live migration through compatible management software.
• Support virtual TPM devices and UEFI firmware through the surrounding virtualization stack.
• Integrate with libvirt, virt-manager and other virtualization management frameworks.
• Expose kernel virtualization interfaces through the KVM API.

Website: www.linux-kvm.org
Support:
Developer: Linux kernel community
License: GNU General Public License v2.0

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