When the same device path is set to multiple devices, i see that pod using multiple devices with same device path comes up fine.

MicroShift Version: 4.20.0_0.nightly_2025_06_02_175911_20250612111214_71d4f99d2
Base OCP Version: 4.20.0-0.nightly-2025-06-02-175911

Always

1. create a device called /dev/testdevice using the command sudo mknod /dev/testdevice c 123 0
2. Add below gdp config into /etc/microshift/config.yaml
genericDevicePlugin:
    status: Enabled
    domain: device.microshift.io
    devices:
      - name: devicea
        groups:
          - paths:
              - path: /dev/testdevice
                mountPath: /dev/mounta
       - name: deviceb
         groups:
           - paths:
               - path: /dev/testdevice
                 mountPath: /dev/mountb
2. Now schedule two pods with devices device.microshift.io/devicea and device.microshift.io/deviceb.
3. Use the pod specs below to configure the pods.
apiVersion: v1
kind: Pod
metadata:
  name: podb
spec:
  containers:
  - name: serial-app-container
    image: registry.access.redhat.com/ubi8/ubi
    command: ["sleep", "3600"] # Keep the container running for an hour
    resources:
      limits:
        device.microshift.io/deviceb: "1" # Request 1 serial device
  restartPolicy: Never 

apiVersion: v1
kind: Pod
metadata:
  name: poda
spec:
  containers:
  - name: serial-app-container
    image: registry.access.redhat.com/ubi8/ubi
    command: ["sleep", "3600"] # Keep the container running for an hour
    resources:
      limits:
        device.microshift.io/devicea: "1" # Request 1 serial device
  restartPolicy: Never 

I see both the pods getting scheduled and comes to running state.

I expect first pod to be running and second pod to be pending state because a pod is already consuming the device which is at that path.

Discussion related to this here: https://redhat-internal.slack.com/archives/C03CJTNLKAT/p1750153046434939