Reza Arbab <arbab@xxxxxxxxxxxxxxxxxx> writes: > On Wed, Oct 26, 2016 at 09:34:18AM +1100, Balbir Singh wrote: >>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 > > The movable_node option is x86-only. Both of those nodes contain normal > memory, so allocations on both are allowed. > >>> 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? > > As far as I know, power has nothing like the SRAT that tells us, at > boot, which memory is hotpluggable. On pseries we have the ibm,dynamic-memory device tree property, which can contain ranges of memory that are not yet "assigned to the partition" - ie. can be hotplugged later. So in general that statement is not true. But I think you're focused on bare-metal, in which case you might be right. But that doesn't mean we couldn't have a similar property, if skiboot/hostboot knew what the ranges of memory were going to be. cheers -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>