Create device nodes in JIT-CDI mode

Signed-off-by: Evan Lezar <[email protected]>

Author: elezar

internal/modifier/cdi.go

@@ -18,6 +18,7 @@ package modifier
 
 import (
 	"fmt"
+	"os/exec"
 	"strings"
 
 	"tags.cncf.io/container-device-interface/pkg/parser"
@@ -28,6 +29,7 @@ import (
 	"github.com/NVIDIA/nvidia-container-toolkit/internal/lookup/root"
 	"github.com/NVIDIA/nvidia-container-toolkit/internal/modifier/cdi"
 	"github.com/NVIDIA/nvidia-container-toolkit/internal/oci"
+	"github.com/NVIDIA/nvidia-container-toolkit/internal/system/nvdevices"
 	"github.com/NVIDIA/nvidia-container-toolkit/pkg/nvcdi"
 	"github.com/NVIDIA/nvidia-container-toolkit/pkg/nvcdi/spec"
 )
@@ -204,6 +206,8 @@ func generateAutomaticCDISpec(logger logger.Interface, cfg *config.Config, drive
 		identifiers = append(identifiers, id)
 	}
 
+	tryCreateDeviceNodes(logger, driver, identifiers...)
+
 	deviceSpecs, err := cdilib.GetDeviceSpecsByID(identifiers...)
 	if err != nil {
 		return nil, fmt.Errorf("failed to get CDI device specs: %w", err)
@@ -221,3 +225,22 @@ func generateAutomaticCDISpec(logger logger.Interface, cfg *config.Config, drive
 		spec.WithClass("gpu"),
 	)
 }
+
+func tryCreateDeviceNodes(logger logger.Interface, driver *root.Driver, identifiers ...string) {
+	devices, err := nvdevices.New(
+		nvdevices.WithLogger(logger),
+		nvdevices.WithDevRoot(driver.Root),
+	)
+	if err != nil {
+		return
+	}
+	if err := devices.CreateNVIDIAControlDevices(); err != nil {
+		logger.Warningf("Failed to create control devices: %v", err)
+	}
+
+	// We run nvidia-smi -L to force the creation of the device nodes.
+	nvidiaSMI := exec.Command("nvidia-smi", "-L")
+	if err := nvidiaSMI.Run(); err != nil {
+		logger.Warningf("Failed to run nvidia-smi: %v", err)
+	}
+}