On Fri, 30 Nov 2018 18:59:21 +0100
David Hildenbrand [off-list ref] wrote:

Let's introduce new types for different kinds of memory blocks and use
them in existing code. As I don't see an easy way to split this up,
do it in one hunk for now.

acpi:
 Use DIMM or DIMM_UNREMOVABLE depending on hotremove support in the kernel.
 Properly change the type when trying to add memory that was already
 detected and used during boot (so this memory will correctly end up as
 "acpi" in user space).

pseries:
 Use DIMM or DIMM_UNREMOVABLE depending on hotremove support in the kernel.
 As far as I see, handling like in the acpi case for existing blocks is
 not required.

probed memory from user space:
 Use DIMM_UNREMOVABLE as there is no interface to get rid of this code
 again.

hv_balloon,xen/balloon:
 Use BALLOON. As simple as that :)

s390x/sclp:
 Use a dedicated type S390X_STANDBY as this type of memory and it's
 semantics are very s390x specific.

powernv/memtrace:
 Only allow to use BOOT memory for memtrace. I consider this code in
 general dangerous, but we have to keep it working ... most probably just
 a debug feature.

I don't think it should be arbitrarily restricted like that.

Thanks

Michal