[PATCH 0/2] disable NUMA affinity reassignments at runtime

[Nathan Lynch <nathanl@linux.ibm.com>]

Changing cpu <-> node relationships at runtime, as the pseries
platform code attempts to do for LPM, PRRN, and VPHN is essentially
unsupported by core subsystems. [1]

While more significant changes (i.e. discarding all that code) likely
are in store, these patches are a minimally invasive way to disable
the problem behavior in a way that should be suitable for backporting
to -stable and distros, and is an improvement on the current
situation.

Note: this doesn't affect use of VPHN at boot time for detecting
shared processor node assignments. Only runtime VPHN-initiated
reassignments are disabled.

[1] E.g. see the discussion here:
    https://lore.kernel.org/lkml/20180831115350.GC8437@linux.vnet.ibm.com/T/#u
 
Nathan Lynch (2):
  powerpc/numa: improve control of topology updates
  powerpc/numa: document topology_updates_enabled, disable by default

 arch/powerpc/mm/numa.c | 32 ++++++++++++++++++++++----------
 1 file changed, 22 insertions(+), 10 deletions(-)

-- 
2.20.1