Tried to reproduce this on B-KVM (4.15.0-1100-kvm) on a kvm instance zeppo, this test suite is failing with the "tpci" test.

It looks like it will hang with PCI bus 00 slot 20:
test_pci   16  TCONF  :  tpci.c:74: PCI bus 00 slot 09 : Test-case '16'
test_pci   17  TPASS  :  PCI bus 00 slot 18 : Test-case '1'
test_pci   18  TPASS  :  PCI bus 00 slot 18 : Test-case '2'
test_pci   19  TPASS  :  PCI bus 00 slot 18 : Test-case '3'
test_pci   20  TPASS  :  PCI bus 00 slot 18 : Test-case '4'
test_pci   21  TPASS  :  PCI bus 00 slot 18 : Test-case '5'
test_pci   22  TPASS  :  PCI bus 00 slot 18 : Test-case '6'
test_pci   23  TPASS  :  PCI bus 00 slot 18 : Test-case '7'
test_pci   24  TPASS  :  PCI bus 00 slot 18 : Test-case '8'
test_pci   25  TPASS  :  PCI bus 00 slot 18 : Test-case '9'
test_pci   26  TPASS  :  PCI bus 00 slot 18 : Test-case '10'
test_pci   27  TPASS  :  PCI bus 00 slot 18 : Test-case '11'
test_pci   28  TPASS  :  PCI bus 00 slot 18 : Test-case '12'
test_pci   29  TPASS  :  PCI bus 00 slot 18 : Test-case '13'
test_pci   30  TPASS  :  PCI bus 00 slot 18 : Test-case '14'
test_pci   31  TPASS  :  PCI bus 00 slot 18 : Test-case '15'
test_pci   32  TCONF  :  tpci.c:74: PCI bus 00 slot 18 : Test-case '16'
test_pci   33  TPASS  :  PCI bus 00 slot 20 : Test-case '1'
test_pci   34  TPASS  :  PCI bus 00 slot 20 : Test-case '2'
test_pci   35  TPASS  :  PCI bus 00 slot 20 : Test-case '3'
test_pci   36  TPASS  :  PCI bus 00 slot 20 : Test-case '4'
test_pci   37  TPASS  :  PCI bus 00 slot 20 : Test-case '5'
test_pci   38  TPASS  :  PCI bus 00 slot 20 : Test-case '6'
test_pci   39  TPASS  :  PCI bus 00 slot 20 : Test-case '7'
test_pci   40  TPASS  :  PCI bus 00 slot 20 : Test-case '8'
test_pci   41  TPASS  :  PCI bus 00 slot 20 : Test-case '9'
test_pci   42  TPASS  :  PCI bus 00 slot 20 : Test-case '10'
test_pci   43  TPASS  :  PCI bus 00 slot 20 : Test-case '11'
(Test hangs here)

Output from virsh console:
Oct 19 08:02:25 zeppo kernel: ltp_tpci: test-case 13
Oct 19 08:02:25 zeppo kernel: ltp_tpci: save state
Oct 19 08:02:25 zeppo kernel: ltp_tpci: saved state of device
Oct 19 08:02:25 zeppo kernel: ltp_tpci: test-case 14
Oct 19 08:02:25 zeppo kernel: ltp_tpci: restore state
Oct 19 08:02:25 zeppo kernel: ltp_tpci: test-case 15
Oct 19 08:02:25 zeppo kernel: ltp_tpci: find device capability
Oct 19 08:02:25 zeppo kernel: ltp_tpci: device has PM capability
Oct 19 08:02:25 zeppo kernel: ltp_tpci: test-case 16
Oct 19 08:02:25 zeppo kernel: ltp_tpci: device doesn't have PCI-EXP capability
Oct 19 08:02:26 zeppo kernel: ltp_tpci: device released
Oct 19 08:02:26 zeppo kernel: 
(no output here, ssh session will not respond at this point. Console is still working, but if you try to do anything it will freeze as well)

$ lspci -nn
00:00.0 Host bridge [0600]: Intel Corporation 440FX - 82441FX PMC [Natoma] [8086:1237] (rev 02)
00:01.0 ISA bridge [0601]: Intel Corporation 82371SB PIIX3 ISA [Natoma/Triton II] [8086:7000]
00:01.1 IDE interface [0101]: Intel Corporation 82371SB PIIX3 IDE [Natoma/Triton II] [8086:7010]
00:01.2 USB controller [0c03]: Intel Corporation 82371SB PIIX3 USB [Natoma/Triton II] [8086:7020] (rev 01)
00:01.3 Bridge [0680]: Intel Corporation 82371AB/EB/MB PIIX4 ACPI [8086:7113] (rev 03)
00:02.0 VGA compatible controller [0300]: Cirrus Logic GD 5446 [1013:00b8]
00:03.0 Unclassified device [00ff]: Red Hat, Inc. Virtio memory balloon [1af4:1002]
00:04.0 Ethernet controller [0200]: Red Hat, Inc. Virtio network device [1af4:1000]
00:05.0 Communication controller [0780]: Red Hat, Inc. Virtio console [1af4:1003]
00:06.0 SCSI storage controller [0100]: Red Hat, Inc. Virtio block device [1af4:1001]
00:07.0 SCSI storage controller [0100]: Red Hat, Inc. Virtio block device [1af4:1001]