test(virtio-mem): add integ test to verify device is detected

Check that the driver correctly detects the virtio-mem device, with the
correct parameters.

Signed-off-by: Riccardo Mancini <[email protected]>

Author: Manciukic

tests/integration_tests/functional/test_memory_hp.py

@@ -0,0 +1,38 @@
+# Copyright 2025 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+# SPDX-License-Identifier: Apache-2.0
+
+"""Tests for verifying the virtio-mem is working correctly"""
+
+
+def test_virtio_mem_detected(uvm_plain_6_1):
+    """
+    Check that the guest kernel has enabled PV steal time.
+    """
+    uvm = uvm_plain_6_1
+    uvm.spawn()
+    uvm.memory_monitor = None
+    uvm.basic_config(
+        boot_args="console=ttyS0 reboot=k panic=1 memhp_default_state=online_movable"
+    )
+    uvm.add_net_iface()
+    uvm.api.memory_hotplug.put(total_size_mib=1024)
+    uvm.start()
+
+    _, stdout, _ = uvm.ssh.check_output("dmesg | grep 'virtio_mem'")
+    for line in stdout.splitlines():
+        _, key, value = line.strip().split(":")
+        key = key.strip()
+        value = int(value.strip(), base=0)
+        match key:
+            case "start address":
+                assert value == (512 << 30), "start address doesn't match"
+            case "region size":
+                assert value == 1024 << 20, "region size doesn't match"
+            case "device block size":
+                assert value == 2 << 20, "block size doesn't match"
+            case "plugged size":
+                assert value == 0, "plugged size doesn't match"
+            case "requested size":
+                assert value == 0, "requested size doesn't match"
+            case _:
+                continue