Description of problem:
Migrate guest with hugepages from 8.3 to 8.4, migration failed with error: qemu-kvm: Failed to load xhci:parent_obj.


Version-Release number of selected component (if applicable):
src host: qemu-img-5.1.0-16.module+el8.3.1+8958+410ab178.x86_64
dst host: qemu-img-5.2.0-2.module+el8.4.0+9186+ec44380f.x86_64


How reproducible:
100%


Steps to Reproduce:
1.Boot guest with cli on src host:
/usr/libexec/qemu-kvm  \
-name "mouse-vm" \
-sandbox off \
-machine q35 \
-device vmcoreinfo \
-cpu IvyBridge-IBRS \
-nodefaults  \
-vga std \
-chardev socket,id=qmp_id_qmpmonitor1,path=/var/tmp/monitor-qmpmonitor1,server,nowait \
-chardev socket,id=qmp_id_catch_monitor,path=/var/tmp/monitor-catch_monitor,server,nowait \
-mon chardev=qmp_id_qmpmonitor1,mode=control \
-mon chardev=qmp_id_catch_monitor,mode=control \
-device pcie-root-port,port=0x10,chassis=1,id=root0,bus=pcie.0,multifunction=on,addr=0x2 \
-device pcie-root-port,port=0x11,chassis=2,id=root1,bus=pcie.0,addr=0x2.0x1 \
-device pcie-root-port,port=0x12,chassis=3,id=root2,bus=pcie.0,addr=0x2.0x2 \
-device pcie-root-port,port=0x13,chassis=4,id=root3,bus=pcie.0,addr=0x2.0x3 \
-device pcie-root-port,port=0x14,chassis=5,id=root4,bus=pcie.0,addr=0x2.0x4 \
-device pcie-root-port,port=0x15,chassis=6,id=root5,bus=pcie.0,addr=0x2.0x5 \
-device pcie-root-port,port=0x16,chassis=7,id=root6,bus=pcie.0,addr=0x2.0x6 \
-device pcie-root-port,port=0x17,chassis=8,id=root7,bus=pcie.0,addr=0x2.0x7 \
-device nec-usb-xhci,id=usb1,bus=root0 \
-device virtio-scsi-pci,id=virtio_scsi_pci0,bus=root1 \
-device scsi-hd,id=image1,drive=drive_image1,bus=virtio_scsi_pci0.0,channel=0,scsi-id=0,lun=0,bootindex=0 \
-device virtio-net-pci,mac=9a:8a:8b:8c:8d:8e,id=net0,vectors=4,netdev=tap0,bus=root2 \
-device usb-tablet,id=usb-tablet1,bus=usb1.0,port=1 \
-blockdev driver=file,cache.direct=on,cache.no-flush=off,filename=/mnt/glusterfs/rhel840-64-virtio-scsi.qcow2,node-name=drive_sys1 \
-blockdev driver=qcow2,node-name=drive_image1,file=drive_sys1 \
-netdev tap,id=tap0,vhost=on \
-m 2560 \
-mem-path /dev/hugepages \
-mem-prealloc \
-overcommit mem-lock=off \
-smp 4,maxcpus=4,cores=2,threads=1,sockets=2 \
-vnc :10 \
-rtc base=utc,clock=host \
-boot menu=off,strict=off,order=cdn,once=c \
-enable-kvm  \
-qmp tcp:0:3333,server,nowait \
-qmp tcp:0:9999,server,nowait \
-qmp tcp:0:9888,server,nowait \
-serial tcp:0:4444,server,nowait \
-monitor stdio \
2.Boot guest with cli on dst host:
/usr/libexec/qemu-kvm  \
-name "mouse-vm" \
-sandbox off \
-machine q35,memory-backend=pc.ram \
-device vmcoreinfo \
-cpu IvyBridge-IBRS \
-nodefaults  \
-vga std \
-chardev socket,id=qmp_id_qmpmonitor1,path=/var/tmp/monitor-qmpmonitor1,server,nowait \
-chardev socket,id=qmp_id_catch_monitor,path=/var/tmp/monitor-catch_monitor,server,nowait \
-mon chardev=qmp_id_qmpmonitor1,mode=control \
-mon chardev=qmp_id_catch_monitor,mode=control \
-device pcie-root-port,port=0x10,chassis=1,id=root0,bus=pcie.0,multifunction=on,addr=0x2 \
-device pcie-root-port,port=0x11,chassis=2,id=root1,bus=pcie.0,addr=0x2.0x1 \
-device pcie-root-port,port=0x12,chassis=3,id=root2,bus=pcie.0,addr=0x2.0x2 \
-device pcie-root-port,port=0x13,chassis=4,id=root3,bus=pcie.0,addr=0x2.0x3 \
-device pcie-root-port,port=0x14,chassis=5,id=root4,bus=pcie.0,addr=0x2.0x4 \
-device pcie-root-port,port=0x15,chassis=6,id=root5,bus=pcie.0,addr=0x2.0x5 \
-device pcie-root-port,port=0x16,chassis=7,id=root6,bus=pcie.0,addr=0x2.0x6 \
-device pcie-root-port,port=0x17,chassis=8,id=root7,bus=pcie.0,addr=0x2.0x7 \
-device nec-usb-xhci,id=usb1,bus=root0 \
-device virtio-scsi-pci,id=virtio_scsi_pci0,bus=root1 \
-device scsi-hd,id=image1,drive=drive_image1,bus=virtio_scsi_pci0.0,channel=0,scsi-id=0,lun=0,bootindex=0 \
-device virtio-net-pci,mac=9a:8a:8b:8c:8d:8e,id=net0,vectors=4,netdev=tap0,bus=root2 \
-device usb-tablet,id=usb-tablet1,bus=usb1.0,port=1 \
-blockdev driver=file,cache.direct=on,cache.no-flush=off,filename=/mnt/glusterfs/rhel840-64-virtio-scsi.qcow2,node-name=drive_sys1 \
-blockdev driver=qcow2,node-name=drive_image1,file=drive_sys1 \
-netdev tap,id=tap0,vhost=on \
-m 2560 \
-object memory-backend-memfd,id=pc.ram,hugetlb=yes,hugetlbsize=2097152,prealloc=yes,size=2684354560 \
-overcommit mem-lock=off \
-smp 4,maxcpus=4,cores=2,threads=1,sockets=2 \
-vnc :10 \
-rtc base=utc,clock=host \
-boot menu=off,strict=off,order=cdn,once=c \
-enable-kvm  \
-qmp tcp:0:3333,server,nowait \
-qmp tcp:0:9999,server,nowait \
-qmp tcp:0:9888,server,nowait \
-serial tcp:0:4444,server,nowait \
-monitor stdio \
-incoming defer \
3.Migrate guest from src to dst host


Actual results:
Migration failed on dst host with error:
(qemu) qemu-kvm: get_pci_config_device: Bad config data: i=0x71 read: a0 device: 0 cmask: ff wmask: 0 w1cmask:0
qemu-kvm: Failed to load PCIDevice:config
qemu-kvm: Failed to load xhci:parent_obj
qemu-kvm: error while loading state for instance 0x0 of device '0000:00:02.0:00.0/xhci'
qemu-kvm: load of migration failed: Invalid argument


Expected results:
Migration succeed


Additional info:
Hit this bz When reproduce bz: Bug 1912201 - qemu-kvm: Unknown ramblock "pc.ram" during migration