Comment 1 for bug 1284874

Based on the trace in the attachment, the sequence of config space accesses leading up to the hang -

vfio: vfio_pci_write_config(0000:03:00.0, @0x78, 0x1, len=0x4)
vfio: vfio_pci_write_config(0000:03:00.0, @0x80, 0x9430, len=0x4)
vfio: vfio_pci_write_config(0000:03:00.0, @0x78, 0xa30c, len=0x4)
vfio: vfio_pci_write_config(0000:03:00.0, @0x80, 0x7fffffff, len=0x4)
vfio: vfio_pci_write_config(0000:03:00.0, @0x78, 0xa5dc, len=0x4)
vfio: vfio_pci_write_config(0000:03:00.0, @0x80, 0x0, len=0x4)
vfio: vfio_pci_write_config(0000:03:00.0, @0x78, 0xa2ec, len=0x4)
vfio: vfio_pci_write_config(0000:03:00.0, @0x80, 0x3, len=0x4)
vfio: vfio_pci_read_config(0000:03:00.0, @0x98, len=0x4) 200
vfio: vfio_pci_write_config(0000:03:00.0, @0x78, 0xa408, len=0x4)
vfio: vfio_pci_read_config(0000:03:00.0, @0x80, len=0x4) 8

vfio: vfio_pci_write_config(0000:03:00.0, @0x78, 0x86420, len=0x4)
vfio: vfio_pci_write_config(0000:03:00.0, @0x80, 0x4, len=0x4)
vfio: vfio_pci_write_config(0000:03:00.0, @0x78, 0x86420, len=0x4)
vfio: vfio_pci_read_config(0000:03:00.0, @0x80, len=0x4) 8

The last 4 writes co-relate to the point where the guest hangs because they get repeated forever