RHEL Engineering is moving the tracking of its product development work on RHEL 6 through RHEL 9 to Red Hat Jira (issues.redhat.com). If you're a Red Hat customer, please continue to file support cases via the Red Hat customer portal. If you're not, please head to the "RHEL project" in Red Hat Jira and file new tickets here. Individual Bugzilla bugs in the statuses "NEW", "ASSIGNED", and "POST" are being migrated throughout September 2023. Bugs of Red Hat partners with an assigned Engineering Partner Manager (EPM) are migrated in late September as per pre-agreed dates. Bugs against components "kernel", "kernel-rt", and "kpatch" are only migrated if still in "NEW" or "ASSIGNED". If you cannot log in to RH Jira, please consult article #7032570. That failing, please send an e-mail to the RH Jira admins at rh-issues@redhat.com to troubleshoot your issue as a user management inquiry. The email creates a ServiceNow ticket with Red Hat. Individual Bugzilla bugs that are migrated will be moved to status "CLOSED", resolution "MIGRATED", and set with "MigratedToJIRA" in "Keywords". The link to the successor Jira issue will be found under "Links", have a little "two-footprint" icon next to it, and direct you to the "RHEL project" in Red Hat Jira (issue links are of type "https://issues.redhat.com/browse/RHEL-XXXX", where "X" is a digit). This same link will be available in a blue banner at the top of the page informing you that that bug has been migrated.

Description of problem:
Test with windows 10 guest, after NIC hot-unplug from host, reboot guest,boot failed.

Version-Release number of selected component (if applicable):
qemu-kvm-1.5.3-101.el7.x86_64
3.10.0-305.el7.x86_64

How reproducible:
100%

Steps to Reproduce:
1.NIC hot-unplug from host
(qemu) device_del net0
(qemu) netdev_del hostnet0
2.Reboot guest

Actual results:
boot fail as attachment

Expected results:
boot success

Additional info:
/usr/libexec/qemu-kvm -name win10qcow2 -M pc-i440fx-rhel7.0.0 -cpu SandyBridge -m 4096 -realtime mlock=off -smp 4 \
-device virtio-scsi-pci,id=scsi2,indirect_desc=off,event_idx=off,bus=pci.0 \
-drive file=/mnt/win10.qcow2,if=none,id=drive-scsi-disk0,format=qcow2 \
-device scsi-hd,bus=scsi2.0,drive=drive-scsi-disk0,id=scsi-disk0,bootindex=1 \
-netdev tap,id=hostnet0  -\
device virtio-net-pci,netdev=hostnet0,id=net0,mac=52:88:66:77:88:66,bus=pci.0,addr=0x3 \
-device qxl-vga,id=video0,ram_size=67108864,vram_size=67108864,vgamem_mb=16,bus=pci.0,addr=0x5 -spice port=6800,disable-ticketing, -monitor stdio -qmp tcp:0:4444,server,nowait

guest img:
http://fileshare.englab.nay.redhat.com/pub/section2/images_backup/rhel7/bug1254855/win10.qcow2
boot fail 
Screenshot:
http://fileshare.englab.nay.redhat.com/pub/section2/images_backup/rhel7/bug1254855/1.png

Test in qemu-img-rhev-2.3.0-18.el7.x86_64 , no this issue

Please check whether the same problem happens if used rtl8139 instead of virtio-net-pci

retest with qemu-kvm-1.5.3-126.el7.x86_64 ,used rtl8139 and virtio-net-pci, all can not reproduced this issue.

seems the result is good.

Please be free to reopen it if there is anything wrong.