Re: [Qemu-devel] [edk2] [PATCH] exec: fix regression by making system-memory region UINT64_MAX size

[Paolo Bonzini]

Il 07/11/2013 22:12, Laszlo Ersek ha scritto:
> 0000000000000000-7ffffffffffffffe (prio 0, RW): system
>   [...]
>   0000000060000000-00000000ffffffff (prio 0, RW): alias pci-hole @pci 
> 0000000060000000-00000000ffffffff
>   [...]
>   00000000ffe00000-00000000ffffffff (prio 0, R-): system.flash
> [...]

Priorities are not "transitive" across aliases; once you use an alias to
map a region, the alias's priority counts, not the target region's
priority.  So the INT_MIN priority for pci-master-abort counts *within
the alias*, but the choice between pci-hole and system.flash is only
affected by the priorities of pci-hole and system.flash.

You could give a smaller priority (-1 or INT_MIN) to pci-hole and just
let it occupy the whole address space, from 0 to UINT64_MAX.  Or perhaps
the pci-hole alias is too large and it should end before the system
flash area.  Both solutions should work.

Paolo