Stephen Hemminger authored Sep 18, 2017 and Adam Jackson committed Sep 20, 2017

The PCI domain may be larger than 16 bits on Microsoft Azure and other
virtual environments. PCI busses reported by ACPI are limited to 16
bits, but in Azure the domain value for pass through devices is
intentionally larger than 16 bits to avoid clashing with local devices.
This is needed to support pass through of GPU devices.

v3: (ajax)
Update FreeBSD and Solaris backends to preserve the full 32-bit domain
number, since on those OSes it stands a chance of working already.
Update NetBSD and OpenBSD backends to initialize domain_16 compatibly
with older libpciaccess; neither backend appears to support more than a
handful of domains to begin with though. Trivially update the generic
x86 backend for source compatibility, though it still only supports one
domain and will never be better.

Fixes: https://bugs.freedesktop.org/show_bug.cgi?id=101744


Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Reviewed-by: Eric Anholt <eric@anholt.net>