On Fri, Jun 26, 2015 at 03:33:29PM +1000, David Gibson wrote: > On Thu, Jun 25, 2015 at 11:44:15AM +0530, Bharata B Rao wrote: > > Currently PowerPC kernel doesn't allow hot-adding memory to memory-less > > node, but instead will silently add the memory to the first node that has > > some memory. This causes two unexpected behaviours for the user. > > > > Memory gets hotplugged to a different node than what the user specified. > > Since pc-dimm subsystem in QEMU still thinks that memory belongs to > > memory-less node, a reboot will set things accordingly and the previously > > hotplugged memory now ends in the right node. This appears as if some > > memory moved from one node to another. > > > > So until kernel starts supporting memory hotplug to memory-less > > nodes, just prevent such attempts upfront in QEMU. > > > > Signed-off-by: Bharata B Rao <bhar...@linux.vnet.ibm.com> > > I presume you're talking about host kernel limitations here?
No, this is a guest kernel limitation. Pls refer to the related discussions about this here: https://lkml.org/lkml/2015/6/24/1 > > If that does get changed in future we'll need some sort of ugly compat > test in qemu to see if the new kernel can handle it, but there's no > way to avoid that, so. Yeah, I see that. Regards, Bharata.
