Re: [PATCH] hw/arm/virt: Validate memory size on the first NUMA node

[Gerd Hoffmann <kraxel@redhat.com>]

  Hi,

> > Unless it architecturally wrong thing i.e. (node size less than 128Mb)
> > ,in which case limiting it in QEMU would be justified, I'd prefer
> > firmware being fixed or it reporting more useful for user error message.
> 
> [include EDK2 developers]
> 
> I don't think 128MB node memory size is architecturally required.
> I also thought EDK2 would be better place to provide a precise error
> mesage and discussed it through with EDK2 developers. Lets see what
> are their thoughts this time.

Useful error reporting that early in the firmware initialization is a
rather hard problem, it's much easier for qemu to catch those problems
and print a useful error message.

Fixing the firmware would be possible.  The firmware simply uses the
memory of the first numa note in the early initialization phase, which
could be changed to look for additional numa nodes.  It's IMHO simply
not worth the trouble though.  numa nodes with less memory than 128M
simply doesn't happen in practice, except when QE does questionable
scaleability testing (scale up the number of numa nodes without also
scaling up the total amount of memory, ending up with rather tiny
numa nodes and a configuration nobody actually uses in practice).

take care,
  Gerd