this does seem to affect ubuntu 18.04 (bionic beaver) as well, meaning it's not possible to host guest vms with the IBRS Security Flag:
qemu-system-x86_64 -cpu ? | grep EPYC-Rome is empty dpkg -l qemu-system Desired=Unknown/Install/Remove/Purge/Hold | Status=Not/Inst/Conf-files/Unpacked/halF-conf/Half-inst/trig-aWait/Trig-pend |/ Err?=(none)/Reinst-required (Status,Err: uppercase=bad) ||/ Name Version Architecture Description +++-=====================================================-===============================-===============================-=============================================================================================================== ii qemu-system 1:4.0+dfsg-0ubuntu9.8 -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1921754 Title: Add missing cpu feature bits in EPYC-Rome model To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/libvirt/+bug/1921754/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs