address copilot comments

Author: slavkap

plugins/hypervisors/kvm/src/main/java/com/cloud/hypervisor/kvm/resource/wrapper/LibvirtRestoreBackupCommandWrapper.java

@@ -432,7 +432,8 @@ private boolean attachRbdVolumeToVm(KVMStoragePoolManager storagePoolMgr, String
 
     private String getDeviceToAttachDisk(String vmName) {
         // --details adds a Type column so cdrom slots (hdc, hdd) can be filtered out — they sort
-        // after the real disks, so without this the last row is always a cdrom, not a free device.
+        // alphabetically ahead of virtio disks, so without this the selected row is a cdrom, not
+        // an actual disk.
         String[] domblkCmd = new String[] { Script.getExecutableAbsolutePath("virsh"), "domblklist", "--domain", vmName, "--details" };
         // The commands are executed without a shell, so the awk program must be passed as a plain
         // argument. Keeping the quotes a shell would have stripped makes awk fail with

plugins/hypervisors/kvm/src/test/java/com/cloud/hypervisor/kvm/resource/wrapper/LibvirtRestoreBackupCommandWrapperTest.java

@@ -30,6 +30,7 @@
 import java.nio.file.Path;
 import java.util.Arrays;
 import java.util.List;
+import java.util.concurrent.atomic.AtomicReference;
 
 import org.apache.cloudstack.backup.BackupAnswer;
 import org.apache.cloudstack.backup.RestoreBackupCommand;
@@ -663,20 +664,23 @@ public void testGetDeviceToAttachDiskPassesUnquotedAwkProgram() throws Exception
     }
 
     @Test
-    public void testGetDeviceToAttachDiskFiltersOutCdromEntries() throws Exception {
+    public void testGetDeviceToAttachDiskRequestsDomblklistDetails() throws Exception {
         try (MockedStatic<Script> scriptMock = mockStatic(Script.class)) {
             scriptMock.when(() -> Script.getExecutableAbsolutePath(anyString()))
                     .thenAnswer(invocation -> invocation.getArgument(0));
-            final List<String[]>[] captured = new List[1];
+            final AtomicReference<List<String[]>> captured = new AtomicReference<>();
             scriptMock.when(() -> Script.executePipedCommands(anyList(), anyLong()))
                     .thenAnswer(invocation -> {
-                        captured[0] = invocation.getArgument(0);
+                        captured.set(invocation.getArgument(0));
                         return new Pair<>(0, "vdb" + System.lineSeparator());
                     });
 
             Assert.assertEquals("vdc", invokeGetDeviceToAttachDisk("test-vm"));
 
-            String[] domblkCmd = captured[0].get(0);
+            // --details adds the Type column the awk program filters on (verified separately in
+            // testGetDeviceToAttachDiskPassesUnquotedAwkProgram); without it cdrom rows can't be
+            // told apart from real disks at all.
+            String[] domblkCmd = captured.get().get(0);
             Assert.assertTrue("domblklist must request --details so the Type column is available to filter on",
                     Arrays.asList(domblkCmd).contains("--details"));
         }