[libvirt] [Question] capabilities.pidfile is left behind while starting and stopping libvirtd repeatly

Hi, all I started and stopped libvirtd service repeatly with high frequency(1 per second), and found that the file capabilities.pidfile is left behind, as well as a qemu process. If I then restart libvirtd, qemu-kvm will fail to start as it's unable to flock capabilities.pidfile's fd. Steps to reproduce the problem: 1. start libvirtd service per second with a shell script. 2. meanwhile, stop libvirtd service per second with another shell script. 3. then, a process qemu is left behind: /usr/bin/qemu-kvm -S -no-user-config -nodefaults -nographic -M none -qmp unix:/var/lib/libvirt/qemu/capabilities.monitor.sock,server,nowait -pidfile /var/lib/libvirt/qemu/capabilities.pidfile -daemonize 4. file /var/lib/libvirt/qemu/capabilities.pidfile is left behind 5. start libvirtd again, the process qemu-kvm fails to start. The cause of the problem: This file is generated by qemu, and deleted by libvirtd. If libvirtd got killed before it removes the pidfile, it would be left behind then. Question: Would it be fine if I kill qemu-kvm process and unlink capabilities.pidfile, just before virQEMUCapsInitQMP runs this qemu-kvm process? -- Best Regards Wang Yufei