22.214.171.124.19. VirtIO PCI Configuration Access BAR Indicator Register (Address: 0x038)
The BAR Indicator field holds the values 0x0 to 0x5 specifying a Base Address register (BAR) belonging to the function located beginning at 10h in PCI Configuration Space. The BAR is used to map the structure into memory space. Any other value is reserved for future use.