What were you trying to do that didn't work?

Detach virtio disk with iommu=on from VM (after there is also virtio interface attached) - depends on order of attach/detach

this can be also tested by run: 

https://libvirt-rhos-jenkins-product.hosted.upshift.rdu2.redhat.com/job/libvirt-RHEL-10.2-runtest-aarch64-function-viommu/11/testReport/rhel/vIOMMU/hotplug_device_with_iommu_enabled_pcie_downstream_port_from_expander_bus_virtio

What is the impact of this issue to you?

Disk & interface not detached, VM will not stop. and has to be destroyed

Please provide the package NVR for which the bug is seen:

kernel-5.14.0-643.el9.aarch64
libvirt-11.9.0-1.el9.aarch64
qemu-kvm-10.1.0-5.el9.aarch64

How reproducible is this bug?:

100%

Steps to reproduce

in separated terminal watch events:

while true; do virsh event --loop --all --timestamp; sleep 1; done

Steps:

1. define & start vm based on attached xml, wait for start

virsh define avocado.xml

2. prepare image for disk:

qemu-img create -f qcow2 /tmp/test.qcow2 200M 

3.attach virtio disk
virsh attach-device vm1 /tmp/dev_obj.xml

<disk type="file" device="disk">
      <driver name="qemu" type="qcow2" iommu="on" />
      <source file="/tmp/test.qcow2" index="2" />
      <backingStore />
      <target dev="vdb" bus="virtio" />
      <alias name="virtio-disk1" />
      <address type="pci" domain="0x0000" bus="0x14" slot="0x00" function="0x0" />
    </disk>
 

4. attach interface
virsh attach-device vm1 /tmp/iface_obj.xml

<interface type="network">
        <model type="virtio" />
        <driver name="vhost" iommu="on" />
        <source network="default" />
        <address type="pci" bus="0x13" />
</interface>

5. detach disk

(optional ... detach iface, shutdown vm)

Expected results:

There is event triggered

There is event triggered
disk is detached and no more in the XML

(if iface is detached - event is also there, iface no more in xml, and user is able to shutdown the VM

Actual results

 no event
disk still in xml
(the iface will still in xml,
and vm not shutdown)

Additional information:

• if the order is "nested" i.e.
   attach dev_obj,
   attach iface_obj,
   detach iface_obj,
   detach dev_obj, the behavior is correct
• in the VM the lsblk after the device-detach will not show the vdb row
• shutdown console info is in the shutdown.log file 
• no error visible in virtqemud.log

The test is not failing on x86_64