tests: Add integration test for virtio-mem device reset

Add a test that verifies virtio-mem device reset works end-to-end by
unbinding and rebinding the guest driver.

Signed-off-by: Ilias Stamatis <ilstam@amazon.com>

Author: ilstam

tests/integration_tests/functional/test_virtio_mem.py

@@ -0,0 +1,31 @@
+# Copyright 2026 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+# SPDX-License-Identifier: Apache-2.0
+"""Tests for virtio-mem device reset."""
+
+
+def test_virtio_mem_device_reset(uvm_plain_any):
+    """
+    Test that virtio-mem device reset works.
+    """
+    vm = uvm_plain_any
+    vm.spawn()
+    vm.basic_config()
+    vm.add_net_iface()
+    vm.api.memory_hotplug.put(total_size_mib=256)
+    vm.start()
+
+    virtio_dev = vm.ssh.check_output(
+        "ls -d /sys/bus/virtio/drivers/virtio_mem/virtio* | xargs -n1 basename"
+    ).stdout.strip()
+
+    vm.ssh.check_output(
+        f"echo {virtio_dev} > /sys/bus/virtio/drivers/virtio_mem/unbind"
+    )
+
+    # Verify the device is gone.
+    ret = vm.ssh.run("ls /sys/bus/virtio/drivers/virtio_mem/virtio*")
+    assert ret.returncode != 0
+
+    # Rebind and verify it's back.
+    vm.ssh.check_output(f"echo {virtio_dev} > /sys/bus/virtio/drivers/virtio_mem/bind")
+    vm.ssh.check_output("ls /sys/bus/virtio/drivers/virtio_mem/virtio*")