Fix #47: Enable hardware acceleration for Linux hosts (KVM)

GitHub Linux runners have been upgraded [1] and now hardware accelerated
nested virtualization is available.

This also removes most logic around accelerators, since QEMU can pick
the best one out of several specified.

[1] https://github.blog/2024-01-17-github-hosted-runners-double-the-power-for-open-source/

changelog.md

@@ -8,6 +8,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Added
 - Add support for FreeBSD 14.0 ([#74](https://github.com/cross-platform-actions/action/issues/74))
 - Add post run step that prints the VM output
+- Support hardware accelerated virtualization on Linux runners ([#47](https://github.com/cross-platform-actions/action/issues/47))
 
 ### Fixed
 - OpenBSD VM fails during "Initializing VM" with QEMU on macOS ([#73](https://github.com/cross-platform-actions/action/issues/73))

readme.md

@@ -233,10 +233,13 @@ they can run.
 | **Linux**                                     | ✅      | ✅      | ✅     | ✅   |
 | **macos-10.15**, **macos-11**, **macos-12**   | ✅      | ✅      | ✅     | ❌   |
 
-macOS runners are, in general, preferred. They support hardware accelerated
-nested virtualization, making them significantly faster than the Linux runners.
-This only applies when the runner architecture and the guest architecture are
-the same, in this case `x86-64`.
+In general the Ubuntu runners are the preferred choice. Both macOS and Ubuntu
+runners support hardware accelerated nested virtualization. But the Ubuntu
+runners have more resources and therefore better performance. Hardware
+acceleration only applies when the runner architecture and the guest
+architecture are the same, in this case `x86-64`. `macos-14` runners which run
+on Apple Silicon does not support hardware accelerated nested virtualization
+and are not supported at all.
 
 ## `Linux on Non-x86 Architectures`
 

spec/operating_systems/freebsd/freebsd.spec.ts

@@ -4,7 +4,6 @@ import FreeBsd from '../../../src/operating_systems/freebsd/freebsd'
 import hostModule from '../../../src/host'
 import * as arch from '../../../src/architecture'
 import * as os from '../../../src/operating_systems/kind'
-import {Accelerator} from '../../../src/vm'
 import * as hypervisor from '../../../src/hypervisor'
 import {Input} from '../../../src/action/input'
 import {Host} from '../../../src/host'
@@ -55,7 +54,6 @@ describe('FreeBSD OperatingSystem', () => {
           ...config,
           ssHostPort: 2847,
           cpu: 'max',
-          accelerator: Accelerator.tcg,
           machineType: 'q35',
           uuid: '864ED7F0-7876-4AA7-8511-816FABCFA87F',
           firmware: `${firmwareDirectory}/share/qemu/bios-256k.bin`

spec/operating_systems/freebsd/qemu_vm.spec.ts

@@ -2,7 +2,6 @@ import {QemuVm} from '../../../src/operating_systems/freebsd/qemu_vm'
 import * as arch from '../../../src/architecture'
 import {host} from '../../../src/host'
 import * as os from '../../../src/operating_systems/kind'
-import {Accelerator} from '../../../src/vm'
 import '../../../src/operating_systems/freebsd/freebsd'
 import {Input} from '../../../src/action/input'
 
@@ -25,7 +24,6 @@ describe('FreeBSD QemuVm', () => {
     diskImage: '',
     ssHostPort: ssHostPort,
     cpu: '',
-    accelerator: Accelerator.tcg,
     machineType: '',
     uuid: '',
     resourcesDiskImage: '',

spec/operating_systems/netbsd/netbsd.spec.ts

@@ -2,7 +2,6 @@ import NetBsd from '../../../src/operating_systems/netbsd/netbsd'
 import * as hostModule from '../../../src/host'
 import * as arch from '../../../src/architecture'
 import * as os from '../../../src/operating_systems/kind'
-import {Accelerator} from '../../../src/vm'
 import HostQemu from '../../../src/host_qemu'
 import * as hypervisor from '../../../src/hypervisor'
 import * as qemu from '../../../src/qemu_vm'
@@ -82,7 +81,6 @@ describe('NetBSD OperatingSystem', () => {
           ...config,
           ssHostPort: 2847,
           cpu: 'max',
-          accelerator: Accelerator.tcg,
           machineType: 'q35',
           uuid: '864ED7F0-7876-4AA7-8511-816FABCFA87F',
           firmware: `${firmwareDirectory}/share/qemu/bios-256k.bin`
@@ -150,7 +148,6 @@ describe('NetBSD OperatingSystem', () => {
             ...config,
             ssHostPort: 2847,
             cpu: 'max',
-            accelerator: Accelerator.hvf,
             machineType: 'q35',
             uuid: '864ED7F0-7876-4AA7-8511-816FABCFA87F',
             firmware: `${firmwareDirectory}/share/qemu/bios-256k.bin`

spec/operating_systems/netbsd/qemu_vm.spec.ts

@@ -2,7 +2,6 @@ import {Vm} from '../../../src/operating_systems/netbsd/qemu_vm'
 import * as arch from '../../../src/architecture'
 import {host} from '../../../src/host'
 import * as os from '../../../src/operating_systems/kind'
-import {Accelerator} from '../../../src/vm'
 import '../../../src/operating_systems/netbsd/netbsd'
 import {Input} from '../../../src/action/input'
 
@@ -25,7 +24,6 @@ describe('NetBSD QemuVm', () => {
     diskImage: '',
     ssHostPort: ssHostPort,
     cpu: '',
-    accelerator: Accelerator.tcg,
     machineType: '',
     uuid: '',
     resourcesDiskImage: '',

src/architecture.ts

@@ -5,7 +5,6 @@ import {ResourceUrls} from './operating_systems/resource_urls'
 import * as os from './operating_systems/kind'
 import OpenBsd from './operating_systems/openbsd/openbsd'
 import {getOrThrow, getOrDefaultOrThrow} from './utility'
-import * as vm from './vm'
 
 export enum Kind {
   arm64,
@@ -50,7 +49,6 @@ export abstract class Architecture {
   abstract get resourceUrl(): string
   abstract get cpu(): string
   abstract get machineType(): string
-  abstract get accelerator(): vm.Accelerator
   abstract get hypervisor(): hypervisor.Hypervisor
   abstract get efiHypervisor(): hypervisor.Hypervisor
 
@@ -100,10 +98,6 @@ export abstract class Architecture {
       return 'virt'
     }
 
-    override get accelerator(): vm.Accelerator {
-      return vm.Accelerator.tcg
-    }
-
     override get hypervisor(): hypervisor.Hypervisor {
       return new hypervisor.Qemu()
     }
@@ -147,10 +141,6 @@ export abstract class Architecture {
       return 'q35'
     }
 
-    override get accelerator(): vm.Accelerator {
-      return this.hostQemu.accelerator
-    }
-
     override get hypervisor(): hypervisor.Hypervisor {
       return this.selectedHypervisor
     }

src/host_qemu.ts

@@ -1,25 +1,14 @@
-import {Accelerator} from './vm'
-
 // Contains host specific QEMU properties
 export default abstract class HostQemu {
   abstract get cpu(): string
-  abstract get accelerator(): Accelerator
 
   static readonly LinuxHostQemu = class extends HostQemu {
-    override get accelerator(): Accelerator {
-      return Accelerator.tcg
-    }
-
     override get cpu(): string {
       return 'max'
     }
   }
 
   static readonly MacosHostQemu = class extends HostQemu {
-    override get accelerator(): Accelerator {
-      return Accelerator.hvf
-    }
-
     override get cpu(): string {
       return 'max'
     }

src/operating_systems/freebsd/freebsd.ts

@@ -67,7 +67,6 @@ export default class FreeBsd extends os.OperatingSystem {
 
       // qemu
       cpu: this.architecture.cpu,
-      accelerator: this.architecture.accelerator,
       machineType: this.architecture.machineType,
 
       // xhyve

src/operating_systems/netbsd/netbsd.ts

@@ -60,7 +60,6 @@ export default class NetBsd extends Qemu {
 
       // qemu
       cpu: this.architecture.cpu,
-      accelerator: this.architecture.accelerator,
       machineType: this.architecture.machineType,
 
       // xhyve

src/operating_systems/openbsd/openbsd.ts

@@ -58,7 +58,6 @@ export default class OpenBsd extends os.OperatingSystem {
 
       // qemu
       cpu: this.architecture.cpu,
-      accelerator: this.architecture.accelerator,
       machineType: this.architecture.machineType,
 
       // xhyve

src/operating_systems/openbsd/qemu_vm.ts

@@ -8,6 +8,12 @@ export class QemuVm extends Vm {
   protected override get netDevive(): string {
     return this.architecture.networkDevice
   }
+
+  protected override get accelerators(): string[] {
+    return this.input.version.startsWith('6')
+      ? ['hvf', 'tcg'] // KVM doesn't work with versions older than 7.0
+      : ['hvf', 'kvm', 'tcg']
+  }
 }
 
 export class QemuVmX86_64 extends QemuVm {

src/qemu_vm.ts

@@ -29,13 +29,13 @@ export abstract class Vm extends vm.Vm {
   }
 
   override get command(): string[] {
-    const accel = vm.Accelerator[this.configuration.accelerator]
+    const accelerators = this.accelerators.join(':')
 
     // prettier-ignore
     return [
       this.hypervisorPath.toString(),
       '-daemonize',
-      '-machine', `type=${this.configuration.machineType},accel=${accel}`,
+      '-machine', `type=${this.configuration.machineType},accel=${accelerators}`,
       '-cpu', this.cpuFlagValue,
       '-smp', this.configuration.cpuCount.toString(),
       '-m', this.configuration.memory,
@@ -85,6 +85,10 @@ export abstract class Vm extends vm.Vm {
     return ['-bios', this.configuration.firmware!.toString()]
   }
 
+  protected get accelerators(): string[] {
+    return ['hvf', 'kvm', 'tcg']
+  }
+
   private get netdev(): string {
     return [
       'user',

src/version.ts

@@ -5,7 +5,7 @@ const version = {
     openbsd: 'v0.7.0'
   },
 
-  resources: 'v0.10.0'
+  resources: 'v0.11.0'
 }
 
 export default version