Unable to detach volume from a running VM - KVM

[Pearl1594]

problem

When attempting to detach a volume from a running VM on KVM it times out with the following exception:

2026-04-13 15:57:11,572 DEBUG [kvm.resource.LibvirtVMDef] (AgentRequest-Handler-2:[]) (logid:4f27dc30) Using informed label [hdc] for volume [null].
2026-04-13 15:57:11,573 DEBUG [kvm.storage.KVMStorageProcessor] (AgentRequest-Handler-2:[]) (logid:4f27dc30) The hypervisor sent the detach command, but it is still possible to identify the device [/mnt/3e518e5c-22d5-3ad2-b036-a8847d93db12/883a6620-6638-4545-b19a-3f0687aefc67] in the instance with UUID [69e2c19f-78a9-4f41-b6bd-30d8c6b3a586].
2026-04-13 15:57:12,575 DEBUG [kvm.resource.LibvirtVMDef] (AgentRequest-Handler-2:[]) (logid:4f27dc30) Using informed label [hdc] for volume [null].
2026-04-13 15:57:12,575 DEBUG [kvm.storage.KVMStorageProcessor] (AgentRequest-Handler-2:[]) (logid:4f27dc30) The hypervisor sent the detach command, but it is still possible to identify the device [/mnt/3e518e5c-22d5-3ad2-b036-a8847d93db12/883a6620-6638-4545-b19a-3f0687aefc67] in the instance with UUID [69e2c19f-78a9-4f41-b6bd-30d8c6b3a586].
2026-04-13 15:57:12,576 DEBUG [kvm.storage.KVMStorageProcessor] (AgentRequest-Handler-2:[]) (logid:4f27dc30) Failed to detach volume [id: 4, uuid: 883a6620-6638-4545-b19a-3f0687aefc67, name: v1, path: 883a6620-6638-4545-b19a-3f0687aefc67], due to com.cloud.exception.InternalErrorException: Could not detach volume after sending the command and waiting for [10000] milliseconds. Probably the VM does not support the sent detach command or the device is busy at the moment. Try again in a couple of minutes.
        at com.cloud.hypervisor.kvm.storage.KVMStorageProcessor.attachOrDetachDevice(KVMStorageProcessor.java:1323)
        at com.cloud.hypervisor.kvm.storage.KVMStorageProcessor.attachOrDetachDisk(KVMStorageProcessor.java:1588)
        at com.cloud.hypervisor.kvm.storage.KVMStorageProcessor.dettachVolume(KVMStorageProcessor.java:1681)
        at com.cloud.storage.resource.StorageSubsystemCommandHandlerBase.execute(StorageSubsystemCommandHandlerBase.java:178)
        at com.cloud.storage.resource.StorageSubsystemCommandHandlerBase.handleStorageCommands(StorageSubsystemCommandHandlerBase.java:73)
        at com.cloud.hypervisor.kvm.resource.wrapper.LibvirtStorageSubSystemCommandWrapper.execute(LibvirtStorageSubSystemCommandWrapper.java:36)
        at com.cloud.hypervisor.kvm.resource.wrapper.LibvirtStorageSubSystemCommandWrapper.execute(LibvirtStorageSubSystemCommandWrapper.java:30)
        at com.cloud.hypervisor.kvm.resource.wrapper.LibvirtRequestWrapper.execute(LibvirtRequestWrapper.java:78)
        at com.cloud.hypervisor.kvm.resource.LibvirtComputingResource.executeRequest(LibvirtComputingResource.java:2282)
        at com.cloud.agent.Agent.processRequest(Agent.java:813)
        at com.cloud.agent.Agent$AgentRequestHandler.doTask(Agent.java:1295)
        at com.cloud.utils.nio.Task.call(Task.java:83)
        at com.cloud.utils.nio.Task.call(Task.java:29)
        at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
        at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1136)
        at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:635)
        at java.base/java.lang.Thread.run(Thread.java:840)

versions

Specific to main (4.23)

The steps to reproduce the bug

1. Create a VM
2. Create a data volume
3. Attach volume to VM
4. Attempt detach volume from the running VM - fails with the above exception

What to do about it?

Should be able to successfully detach the volume as it did in the older CloudStack versions