[PATCH 0/2] mm: remove CONFIG_ARCH_ENABLE_MEMORY_HOTREMOVE and cleanup CONFIG_MIGRATION

From: "David Hildenbrand (Arm)" <david@kernel.org>
To: linux-kernel@vger.kernel.org
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	 "David Hildenbrand (Arm)" <david@kernel.org>
Subject: [PATCH 0/2] mm: remove CONFIG_ARCH_ENABLE_MEMORY_HOTREMOVE and cleanup CONFIG_MIGRATION
Date: Thu, 19 Mar 2026 09:19:39 +0100	[thread overview]
Message-ID: <20260319-config_migration-v1-0-42270124966f@kernel.org> (raw)

While working on memory hotplug code cleanups, I realized that
CONFIG_ARCH_ENABLE_MEMORY_HOTREMOVE is not really required anymore.

Changing that revealed some rather nasty looking CONFIG_MIGRATION
handling.

Let's clean that up by introducing a dedicated CONFIG_NUMA_MIGRATION
option and reducing the dependencies that CONFIG_MIGRATION has.

Heavily cross compiled. I assume these changes are fine, but messing
with kconfig sometimes feels like playing with fire :)

Signed-off-by: David Hildenbrand (Arm) <david@kernel.org>
---
David Hildenbrand (Arm) (2):
      mm: remove CONFIG_ARCH_ENABLE_MEMORY_HOTREMOVE
      mm: introduce CONFIG_NUMA_MIGRATION and simplify CONFIG_MIGRATION

 arch/arm64/Kconfig           |  1 -
 arch/loongarch/Kconfig       |  1 -
 arch/powerpc/Kconfig         |  1 -
 arch/riscv/Kconfig           |  1 -
 arch/s390/Kconfig            |  1 -
 arch/x86/Kconfig             |  1 -
 include/linux/memory-tiers.h |  2 +-
 init/Kconfig                 |  2 +-
 mm/Kconfig                   | 33 +++++++++++++++------------------
 mm/memory-tiers.c            | 12 ++++++------
 mm/mempolicy.c               |  2 +-
 mm/migrate.c                 |  5 ++---
 12 files changed, 26 insertions(+), 36 deletions(-)
---
base-commit: fbf55982f31ae6aa11f890c36bccc130ce70a312
change-id: 20260317-config_migration-463e20400499

Best regards,
-- 
David Hildenbrand (Arm) <david@kernel.org>