Description of problem:
We have upgraded our systems from advanced-virtualization stack to the latest packages provided by CentOS Stream 8 (AppStream).

Essentially:
qemu-kvm-6.0.0-3[13].el8s → qemu-kvm-6.1.0-4.module_el8.6.0+983+a7505f3f
libvirt-7.6.0-[1-6].el8s → libvirt-7.9.0-1.module_el8.6.0+983+a7505f3f

And now start any VM does not actually do anything useful, console keeps being empty and VM does not come up. It shows as running in virsh list, but otherwise it does not do anything.

***Simply downgrading packages back to the previous versions and stop/start VM fixes the issue.***

Version-Release number of selected component (if applicable):
qemu-kvm-6.1.0-4.module_el8.6.0+983+a7505f3f.x86_64
libvirt-7.9.0-1.module_el8.6.0+983+a7505f3f.x86_64


How reproducible:
Always.

Steps to Reproduce:
1. Spawn a VM
2. Try to check "virsh console" or try to check if a VM is alive (e.g. by ping/ssh or any other means)

Actual results:
VM is not really running.

Expected results:
VM is working as before.

Additional info:
Here's the full cmdline of the qemu-kvm process (spawned by libvirt, created by the OpenStack):
1806324 ?        Sl     0:04 /usr/libexec/qemu-kvm -name guest=instance-0003e769,debug-threads=on -S -object {"qom-type":"secret","id":"masterKey0","format":"raw","file":"/var/lib/libvirt/qemu/domain-1-instance-0003e769/master-key.aes"} -machine pc-q35-rhel8.5.0,accel=kvm,usb=off,dump-guest-core=off -cpu host,migratable=on -m 20480 -overcommit mem-lock=off -smp 2,sockets=1,dies=1,cores=1,threads=2 -object {"qom-type":"iothread","id":"iothread1"} -object {"qom-type":"iothread","id":"iothread2"} -object {"qom-type":"memory-backend-file","id":"ram-node0","mem-path":"/dev/hugepages/libvirt/qemu/1-instance-0003e769","share":true,"prealloc":true,"size":21474836480,"host-nodes":[0],"policy":"bind"} -numa node,nodeid=0,cpus=0-1,memdev=ram-node0 -uuid 3f7ed13b-c7ee-4e7c-8651-fbe74234eb70 -smbios type=1,manufacturer=RDO,product=OpenStack Compute,version=0.0.0-1.el8+gdc,serial=3f7ed13b-c7ee-4e7c-8651-fbe74234eb70,uuid=3f7ed13b-c7ee-4e7c-8651-fbe74234eb70,family=Virtual Machine -no-user-config -nodefaults -chardev socket,id=charmonitor,fd=37,server=on,wait=off -mon chardev=charmonitor,id=monitor,mode=control -rtc base=utc,driftfix=slew -global kvm-pit.lost_tick_policy=delay -no-hpet -no-shutdown -boot strict=on -device pcie-root-port,port=16,chassis=1,id=pci.1,bus=pcie.0,multifunction=on,addr=0x2 -device pcie-root-port,port=17,chassis=2,id=pci.2,bus=pcie.0,addr=0x2.0x1 -device pcie-root-port,port=18,chassis=3,id=pci.3,bus=pcie.0,addr=0x2.0x2 -device pcie-root-port,port=19,chassis=4,id=pci.4,bus=pcie.0,addr=0x2.0x3 -device pcie-root-port,port=20,chassis=5,id=pci.5,bus=pcie.0,addr=0x2.0x4 -device pcie-root-port,port=21,chassis=6,id=pci.6,bus=pcie.0,addr=0x2.0x5 -device pcie-root-port,port=22,chassis=7,id=pci.7,bus=pcie.0,addr=0x2.0x6 -device pcie-root-port,port=23,chassis=8,id=pci.8,bus=pcie.0,addr=0x2.0x7 -device pcie-root-port,port=24,chassis=9,id=pci.9,bus=pcie.0,multifunction=on,addr=0x3 -device pcie-root-port,port=25,chassis=10,id=pci.10,bus=pcie.0,addr=0x3.0x1 -device pcie-root-port,port=26,chassis=11,id=pci.11,bus=pcie.0,addr=0x3.0x2 -device pcie-root-port,port=27,chassis=12,id=pci.12,bus=pcie.0,addr=0x3.0x3 -device pcie-root-port,port=28,chassis=13,id=pci.13,bus=pcie.0,addr=0x3.0x4 -device pcie-root-port,port=29,chassis=14,id=pci.14,bus=pcie.0,addr=0x3.0x5 -device pcie-root-port,port=30,chassis=15,id=pci.15,bus=pcie.0,addr=0x3.0x6 -device pcie-root-port,port=31,chassis=16,id=pci.16,bus=pcie.0,addr=0x3.0x7 -device pcie-root-port,port=32,chassis=17,id=pci.17,bus=pcie.0,addr=0x4 -device pcie-pci-bridge,id=pci.18,bus=pci.1,addr=0x0 -device piix3-usb-uhci,id=usb,bus=pci.18,addr=0x1 -blockdev {"driver":"host_device","filename":"/dev/volumes/3f7ed13b-c7ee-4e7c-8651-fbe74234eb70_disk","aio":"native","node-name":"libvirt-3-storage","cache":{"direct":true,"no-flush":false},"auto-read-only":true,"discard":"unmap"} -blockdev {"node-name":"libvirt-3-format","read-only":false,"cache":{"direct":true,"no-flush":false},"driver":"raw","file":"libvirt-3-storage"} -device virtio-blk-pci,iothread=iothread1,bus=pci.4,addr=0x0,drive=libvirt-3-format,id=virtio-disk0,bootindex=1,write-cache=on -blockdev {"driver":"host_device","filename":"/dev/volumes/3f7ed13b-c7ee-4e7c-8651-fbe74234eb70_disk.eph0","aio":"native","node-name":"libvirt-2-storage","cache":{"direct":true,"no-flush":false},"auto-read-only":true,"discard":"unmap"} -blockdev {"node-name":"libvirt-2-format","read-only":false,"cache":{"direct":true,"no-flush":false},"driver":"raw","file":"libvirt-2-storage"} -device virtio-blk-pci,iothread=iothread1,bus=pci.5,addr=0x0,drive=libvirt-2-format,id=virtio-disk1,write-cache=on -blockdev {"driver":"file","filename":"/var/lib/nova/instances/3f7ed13b-c7ee-4e7c-8651-fbe74234eb70/disk.config","node-name":"libvirt-1-storage","cache":{"direct":true,"no-flush":false},"auto-read-only":true,"discard":"unmap"} -blockdev {"node-name":"libvirt-1-format","read-only":true,"cache":{"direct":true,"no-flush":false},"driver":"raw","file":"libvirt-1-storage"} -device ide-cd,bus=ide.0,drive=libvirt-1-format,id=sata0-0-0,write-cache=on -netdev tap,fd=39,id=hostnet0,vhost=on,vhostfd=41 -device virtio-net-pci,host_mtu=9000,netdev=hostnet0,id=net0,mac=fa:16:3e:0f:68:e2,bus=pci.2,addr=0x0 -netdev tap,fd=42,id=hostnet1,vhost=on,vhostfd=43 -device virtio-net-pci,host_mtu=9000,netdev=hostnet1,id=net1,mac=fa:16:3e:f3:86:d7,bus=pci.3,addr=0x0 -add-fd set=5,fd=45 -chardev pty,id=charserial0,logfile=/dev/fdset/5,logappend=on -device isa-serial,chardev=charserial0,id=serial0 -device usb-tablet,id=input0,bus=usb.0,port=1 -audiodev id=audio1,driver=none -vnc 10.12.48.177:0,audiodev=audio1 -device cirrus-vga,id=video0,bus=pcie.0,addr=0x1 -device virtio-balloon-pci,id=balloon0,bus=pci.6,addr=0x0 -object {"qom-type":"rng-random","id":"objrng0","filename":"/dev/urandom"} -device virtio-rng-pci,rng=objrng0,id=rng0,bus=pci.7,addr=0x0 -global virtio-blk-pci.config-wce=off -sandbox on,obsolete=deny,elevateprivileges=deny,spawn=deny,resourcecontrol=deny -msg timestamp=on

And strace on this process does not show anything useful (in opposite, it is quite silent):
[NA1][CHECK][root@cmp0078 3f7ed13b-c7ee-4e7c-8651-fbe74234eb70]# strace -fff -p 1806324
strace: Process 1806324 attached with 8 threads
[pid 1806385] futex(0x55c35cf14278, FUTEX_WAIT_PRIVATE, 0, NULL <unfinished ...>
[pid 1806376] futex(0x55c35c9751c0, FUTEX_WAKE_PRIVATE, 1 <unfinished ...>
[pid 1806375] futex(0x55c35c9751c0, FUTEX_WAIT_PRIVATE, 2, NULL <unfinished ...>
[pid 1806374] restart_syscall(<... resuming interrupted read ...> <unfinished ...>
[pid 1806356] ppoll([{fd=15, events=POLLIN|POLLERR|POLLHUP}], 1, NULL, NULL, 8 <unfinished ...>
[pid 1806354] ppoll([{fd=12, events=POLLIN|POLLERR|POLLHUP}], 1, NULL, NULL, 8 <unfinished ...>
[pid 1806349] futex(0x55c35c9941c8, FUTEX_WAIT, 4294967295, NULL <unfinished ...>
[pid 1806324] ppoll([{fd=4, events=POLLIN}, {fd=7, events=POLLIN}, {fd=9, events=POLLIN}, {fd=10, events=POLLIN}, {fd=22, events=POLLIN}, {fd=23, events=POLLIN}], 6, {tv_sec=0, tv_nsec=220919453}, NULL, 8 <unfinished ...>
[pid 1806376] <... futex resumed>)      = 0
[pid 1806375] <... futex resumed>)      = -1 EAGAIN (Resource temporarily unavailable)
[pid 1806376] ioctl(38, KVM_RUN <unfinished ...>
[pid 1806375] futex(0x55c35c9751c0, FUTEX_WAKE_PRIVATE, 1) = 0
[pid 1806375] ioctl(36, KVM_RUN <unfinished ...>
[pid 1806324] <... ppoll resumed>)      = 0 (Timeout)
[pid 1806324] ppoll([{fd=4, events=POLLIN}, {fd=7, events=POLLIN}, {fd=9, events=POLLIN}, {fd=10, events=POLLIN}, {fd=22, events=POLLIN}, {fd=23, events=POLLIN}], 6, {tv_sec=0, tv_nsec=0}, NULL, 8) = 0 (Timeout)
[pid 1806324] ppoll([{fd=4, events=POLLIN}, {fd=7, events=POLLIN}, {fd=9, events=POLLIN}, {fd=10, events=POLLIN}, {fd=22, events=POLLIN}, {fd=23, events=POLLIN}], 6, {tv_sec=0, tv_nsec=457839868}, NULL, 8) = 0 (Timeout)
[pid 1806324] ppoll([{fd=4, events=POLLIN}, {fd=7, events=POLLIN}, {fd=9, events=POLLIN}, {fd=10, events=POLLIN}, {fd=22, events=POLLIN}, {fd=23, events=POLLIN}], 6, {tv_sec=0, tv_nsec=0}, NULL, 8) = 0 (Timeout)
[pid 1806324] ppoll([{fd=4, events=POLLIN}, {fd=7, events=POLLIN}, {fd=9, events=POLLIN}, {fd=10, events=POLLIN}, {fd=22, events=POLLIN}, {fd=23, events=POLLIN}], 6, {tv_sec=2, tv_nsec=537702149}, NULL, 8) = 0 (Timeout)
[pid 1806324] ppoll([{fd=4, events=POLLIN}, {fd=7, events=POLLIN}, {fd=9, events=POLLIN}, {fd=10, events=POLLIN}, {fd=22, events=POLLIN}, {fd=23, events=POLLIN}], 6, {tv_sec=0, tv_nsec=0}, NULL, 8) = 0 (Timeout)
[pid 1806324] ppoll([{fd=4, events=POLLIN}, {fd=7, events=POLLIN}, {fd=9, events=POLLIN}, {fd=10, events=POLLIN}, {fd=22, events=POLLIN}, {fd=23, events=POLLIN}], 6, {tv_sec=2, tv_nsec=998020126}, NULL, 8) = 0 (Timeout)
[pid 1806324] ppoll([{fd=4, events=POLLIN}, {fd=7, events=POLLIN}, {fd=9, events=POLLIN}, {fd=10, events=POLLIN}, {fd=22, events=POLLIN}, {fd=23, events=POLLIN}], 6, {tv_sec=0, tv_nsec=0}, NULL, 8) = 0 (Timeout)
[pid 1806324] ppoll([{fd=4, events=POLLIN}, {fd=7, events=POLLIN}, {fd=9, events=POLLIN}, {fd=10, events=POLLIN}, {fd=22, events=POLLIN}, {fd=23, events=POLLIN}], 6, {tv_sec=2, tv_nsec=998577848}, NULL, 8) = 0 (Timeout)
[pid 1806324] ppoll([{fd=4, events=POLLIN}, {fd=7, events=POLLIN}, {fd=9, events=POLLIN}, {fd=10, events=POLLIN}, {fd=22, events=POLLIN}, {fd=23, events=POLLIN}], 6, {tv_sec=0, tv_nsec=0}, NULL, 8) = 0 (Timeout)
[pid 1806324] ppoll([{fd=4, events=POLLIN}, {fd=7, events=POLLIN}, {fd=9, events=POLLIN}, {fd=10, events=POLLIN}, {fd=22, events=POLLIN}, {fd=23, events=POLLIN}], 6, {tv_sec=1, tv_nsec=448096579}, NULL, 8^Cstrace: Process 1806324 detached
 <detached ...>
strace: Process 1806349 detached
strace: Process 1806354 detached
strace: Process 1806356 detached
strace: Process 1806374 detached
strace: Process 1806375 detached
strace: Process 1806376 detached
strace: Process 1806385 detached