Support for native KVM inside pelican wings!

config/config.go

@@ -788,6 +788,44 @@ func UseOpenat2() bool {
 	}
 }
 
+// IsKVMAvailable checks if KVM is available on the host system by checking
+// if /dev/kvm exists and is accessible.
+func IsKVMAvailable() bool {
+	// Check if /dev/kvm exists
+	if _, err := os.Stat("/dev/kvm"); err != nil {
+		if os.IsNotExist(err) {
+			log.Debug("/dev/kvm not found: KVM is not available on this system")
+			return false
+		}
+		// Other errors from Stat (e.g., permission issues checking the file)
+		log.WithError(err).Warn("/dev/kvm stat failed: unexpected error, assuming KVM not available")
+		return false
+	}
+
+	// Try to open the device to verify it's actually accessible
+	file, err := os.Open("/dev/kvm")
+	if err != nil {
+		if os.IsPermission(err) {
+			// KVM device exists but we don't have permission to access it
+			// Return true since KVM is present, just not accessible to this process
+			log.Info("/dev/kvm permission denied: KVM is present but not accessible to this process")
+			return true
+		}
+		if os.IsNotExist(err) {
+			// Shouldn't happen if Stat succeeded, but handle it anyway
+			log.Debug("/dev/kvm not found: KVM is not available on this system")
+			return false
+		}
+		// Other unexpected errors
+		log.WithError(err).Warn("/dev/kvm open failed: unexpected error, assuming KVM not available")
+		return false
+	}
+	defer file.Close()
+
+	log.Debug("/dev/kvm is available and accessible")
+	return true
+}
+
 // Expand expands an input string by calling [os.ExpandEnv] to expand all
 // environment variables, then checks if the value is prefixed with `file://`
 // to support reading the value from a file.

config/config_docker.go

@@ -96,6 +96,10 @@ type DockerConfiguration struct {
 		Type   string            `default:"local" json:"type" yaml:"type"`
 		Config map[string]string `default:"{\"max-size\":\"5m\",\"max-file\":\"1\",\"compress\":\"false\",\"mode\":\"non-blocking\"}" json:"config" yaml:"config"`
 	} `json:"log_config" yaml:"log_config"`
+
+	// EnableNativeKVM enables native KVM support for containers. This allows containers
+	// to access /dev/kvm for hardware-accelerated virtualization. Defaults to false.
+	EnableNativeKVM bool `default:"false" json:"enable_native_kvm" yaml:"enable_native_kvm"`
 }
 
 func (c DockerConfiguration) ContainerLogConfig() container.LogConfig {

environment/settings.go

@@ -133,6 +133,17 @@ func (l Limits) AsContainerResources() container.Resources {
 		resources.CpusetCpus = l.Threads
 	}
 
+	// Add KVM device mapping if native KVM support is enabled
+	if config.Get().Docker.EnableNativeKVM {
+		kvmDevice := container.DeviceMapping{
+			PathOnHost:        "/dev/kvm",
+			PathInContainer:   "/dev/kvm",
+			CgroupPermissions: "rwm",
+		}
+		// Append to existing devices slice (append handles nil slices safely)
+		resources.Devices = append(resources.Devices, kvmDevice)
+	}
+
 	return resources
 }