tests: skip the test if it cannot create a loopback device

Seems our x86_64 CI host doesn't have enough loopback devices.

Signed-off-by: Kazuyoshi Kato <[email protected]>

Author: kzys

tests/integration_tests/functional/test_drives.py

@@ -4,7 +4,7 @@
 
 import os
 import platform
-from subprocess import run
+from subprocess import run, CalledProcessError
 
 import pytest
 
@@ -96,7 +96,10 @@ def test_rescan_dev(test_microvm_with_ssh, network_config):
     # https://github.com/firecracker-microvm/firecracker-containerd/issues/141
     loopback_device = f'/dev/loop{os.getpid()}'
     losetup = ['losetup', loopback_device, fs2.path]
-    run(losetup, check=True)
+    try:
+        run(losetup, check=True)
+    except CalledProcessError:
+        pytest.skip("the kernel doesn't have enough loopback devices")
 
     try:
         response = test_microvm.drive.patch(