[libvirt-users] unable to add pci network to existing vm

Greetings, I'm trying to add a virtual nic to an existing and active vm and I'm getting this error: error: internal error: No more available PCI slots the cmd I'm trying to run is: virsh -c qemu:///system attach-interface --domain router --type bridge --source virbr0 --model virtio --config --live the lspci output within the vm is this: # lspci 00:00.0 Host bridge: Intel Corporation 82G33/G31/P35/P31 Express DRAM Controller 00:01.0 PCI bridge: Intel Corporation 7500/5520/5500/X58 I/O Hub PCI Express Root Port 0 (rev 02) 00:01.1 PCI bridge: Intel Corporation 7500/5520/5500/X58 I/O Hub PCI Express Root Port 0 (rev 02) 00:01.2 PCI bridge: Intel Corporation 7500/5520/5500/X58 I/O Hub PCI Express Root Port 0 (rev 02) 00:01.3 PCI bridge: Intel Corporation 7500/5520/5500/X58 I/O Hub PCI Express Root Port 0 (rev 02) 00:01.4 PCI bridge: Intel Corporation 7500/5520/5500/X58 I/O Hub PCI Express Root Port 0 (rev 02) 00:01.5 PCI bridge: Intel Corporation 7500/5520/5500/X58 I/O Hub PCI Express Root Port 0 (rev 02) 00:01.6 PCI bridge: Intel Corporation 7500/5520/5500/X58 I/O Hub PCI Express Root Port 0 (rev 02) 00:1d.0 USB controller: Intel Corporation 82801I (ICH9 Family) USB UHCI Controller #1 (rev 03) 00:1d.1 USB controller: Intel Corporation 82801I (ICH9 Family) USB UHCI Controller #2 (rev 03) 00:1d.2 USB controller: Intel Corporation 82801I (ICH9 Family) USB UHCI Controller #3 (rev 03) 00:1d.7 USB controller: Intel Corporation 82801I (ICH9 Family) USB2 EHCI Controller #1 (rev 03) 00:1e.0 PCI bridge: Intel Corporation 82801 PCI Bridge (rev 92) 00:1f.0 ISA bridge: Intel Corporation 82801IB (ICH9) LPC Interface Controller (rev 02) 00:1f.2 SATA controller: Intel Corporation 82801IR/IO/IH (ICH9R/DO/DH) 6 port SATA Controller [AHCI mode] (rev 02) 00:1f.3 SMBus: Intel Corporation 82801I (ICH9 Family) SMBus Controller (rev 02) 00:1f.6 Ethernet controller: Intel Corporation Ethernet Connection (2) I219-V (rev 31) 01:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller (rev 06) 02:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller (rev 06) 03:00.0 SCSI storage controller: Red Hat, Inc. Virtio block device (rev 01) 04:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller (rev 06) 05:00.0 Unclassified device [00ff]: Red Hat, Inc. Virtio memory balloon (rev 01) 06:00.0 Ethernet controller: Red Hat, Inc. Virtio network device (rev 01) 07:00.0 Unclassified device [0002]: Red Hat, Inc. Virtio filesystem (rev 01) 08:00.0 PCI bridge: Red Hat, Inc. QEMU PCI-PCI bridge how can I add additional pci entry? I don't mind if I need to edit the xml file and restart the vm, I just don't want to cause the vm not to start due to bad xml or something. Thanks, Dagg.