On 26/10/16 02:55, Reza Arbab wrote:

On Tue, Oct 25, 2016 at 11:15:40PM +1100, Balbir Singh wrote:

quoted

After the ack, I realized there were some more checks needed, IOW
questions for you :)

Hey! No takebacks!

I still believe we need your changes, I was wondering if we've tested
it against normal memory nodes and checked if any memblock
allocations end up there. Michael showed me some memblock
allocations on node 1 of a two node machine with movable_node
I'll double check at my end. See my question below

The short answer is that neither of these is a concern.

Longer; if you use "movable_node", x86 can identify these nodes at boot. They call memblock_mark_hotplug() while parsing the SRAT. Then, when the zones are initialized, those markings are used to determine ZONE_MOVABLE.

We have no analog of this SRAT information, so our movable nodes can only be created post boot, by hotplugging and explicitly onlining with online_movable.

Is this true for all of system memory as well or only for nodes
hotplugged later?

Balbir Singh.