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

Libvirt report post copy migration resume failed but actually success in some cases

What is the impact of this issue to you?

Libvirt report an error when resume a post copy migration in some cases

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

libvirt-10.10.0-3.el9.x86_64
qemu-kvm-9.1.0-5.el9.x86_64

How reproducible is this bug?:

100% in automation environment

Steps to reproduce

1. prepare a migration environment and an active vm
# virsh start vm1
Domain 'vm1' started

2. perform postcopy migration and abort migration
Terminal1:
# virsh migrate --live --p2p --verbose --domain vm1 --desturi qemu+tcp://target_host/system  --postcopy --bandwidth 5 --tls

Terminal2:
virsh # migrate-postcopy vm1
virsh # domjobabort vm1 --postcopy

3. resume postcopy migration
# virsh migrate --live --p2p --verbose --domain vm1 --desturi qemu+tcp://target_host/system  --postcopy --bandwidth 5 --tls --postcopy-resume
error: operation failed: job 'migration in' failed in post-copy phase

4. After a few minutes, the guest was running on target host and shutdown on the source guest
# virsh list --all
 Id   Name   State
----------------------
 2    vm1    running

5. check target host virtqemud log and can find that post-copy resume actually success

Expected results

Should not report error if recover successfully.

Actual results

Recover postcopy returned with error '"job 'migration in' failed in post-copy phase' but the migration was recovered successfully in fact.

Additional info

This issue not happened on every test environment. I compared the different between the "good" and "bad" environment and found that looks like in the "bad" environment qemu sent postcopy-recover event later than the "good" environment.