Those devices show up as /sys/devices/vif-N, let's use that number
to name them enXN.
Without this, all schemes fail and they keep the kernel names, which can
be racy.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The current detection code relies on /sys/firmware/dmi/entries/0-0/raw
to disambiguate Amazon EC2 virtualized from metal instances.
Unfortunately this file is root only. Thus on a c6g.metal instance
(aarch64), we observe something like this:
$ systemd-detect-virt
amazon
$ sudo systemd-detect-virt
none
Only the latter is correct.
The right long term fix is to extend the kernel to expose the SMBIOS BIOS
Characteristics properly via /sys/class/dmi, but until this happens (and
for backwards compatibility when it does), we need a plan B.
This change implements such a workaround by falling back to using the
instance type from DMI and looking at the ".metal" string present on
metal instances.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>