From f81faad0a15190c85b6668ac4416b1e4a78854fd Mon Sep 17 00:00:00 2001
From: Pascal Scholz <pascal.scholz@cyberus-technology.de>
Date: Thu, 26 Mar 2026 11:48:03 +0100
Subject: [PATCH] tests: Add an integration test to check duplicate PCI device
 IDs

This integration test verifies that the same device ID cannot be
allocated twice. Moreover, we check that the returned error matches our
expectations.

Signed-off-by: Pascal Scholz <pascal.scholz@cyberus-technology.de>
On-behalf-of: SAP pascal.scholz@sap.com
Signed-off-by: Rob Bradford <rbradford@meta.com>
---
 cloud-hypervisor/tests/integration.rs | 78 +++++++++++++++++++++++++++
 1 file changed, 78 insertions(+)

diff --git a/cloud-hypervisor/tests/integration.rs b/cloud-hypervisor/tests/integration.rs
index 54394903c..51d4b06e8 100644
--- a/cloud-hypervisor/tests/integration.rs
+++ b/cloud-hypervisor/tests/integration.rs
@@ -5837,6 +5837,84 @@ mod common_parallel {
 
         handle_child_output(r, &output);
     }
+
+    #[test]
+    // Test that adding a duplicate PCI device ID fails
+    fn test_duplicate_pci_device_id() {
+        let disk_config = UbuntuDiskConfig::new(JAMMY_IMAGE_NAME.to_string());
+        let guest = Guest::new(Box::new(disk_config));
+
+        #[cfg(target_arch = "x86_64")]
+        let kernel_path = direct_kernel_boot_path();
+        #[cfg(target_arch = "aarch64")]
+        let kernel_path = edk2_path();
+
+        let api_socket = temp_api_path(&guest.tmp_dir);
+
+        // Boot without network
+        let mut cmd = GuestCommand::new(&guest);
+
+        cmd.args(["--api-socket", &api_socket])
+            .default_cpus()
+            .default_memory()
+            .args(["--kernel", kernel_path.to_str().unwrap()])
+            .args(["--cmdline", DIRECT_KERNEL_BOOT_CMDLINE])
+            .default_net()
+            .default_disks()
+            .capture_output();
+
+        let mut child = cmd.spawn().unwrap();
+
+        guest.wait_vm_boot().unwrap();
+
+        // Add a network device with non-static device ID request
+        let r = std::panic::catch_unwind(|| {
+            let (cmd_success, cmd_stdout, _) = remote_command_w_output(
+                &api_socket,
+                "add-net",
+                Some(
+                    format!(
+                        "id=test0,tap=,mac={},ip={},mask=255.255.255.128",
+                        guest.network.guest_mac1, guest.network.host_ip1,
+                    )
+                    .as_str(),
+                ),
+            );
+            assert!(cmd_success);
+
+            // We now know the first free device ID on the bus
+            let output = String::from_utf8(cmd_stdout).expect("should work");
+            let (_, _, first_free_device_id, _) = bdf_from_hotplug_response(output.as_str());
+            assert_ne!(first_free_device_id, 0);
+
+            let (cmd_success, _, cmd_stderr) = remote_command_w_output(
+                &api_socket,
+                "add-net",
+                Some(
+                    format!(
+                        "id=test1337,tap=,mac={},ip={},mask=255.255.255.128,pci_device_id={first_free_device_id}",
+                        guest.network.guest_mac1, guest.network.host_ip1,
+                    )
+                    .as_str(),
+                ),
+            );
+            // Check for fail; Allocating the same device ID for two devices is disallowed
+            assert!(!cmd_success);
+            // Check that the error message contains the expected error
+            let std_err_str = String::from_utf8(cmd_stderr).unwrap();
+            assert!(
+                std_err_str.contains(&format!(
+                    "Valid PCI device identifier but already used: {first_free_device_id}"
+                )),
+                "Command return was: {std_err_str}"
+            );
+        });
+
+        kill_child(&mut child);
+        let output = child.wait_with_output().unwrap();
+
+        handle_child_output(r, &output);
+    }
 }
 
 mod dbus_api {