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

From: Jonathan Cameron <jonathan.cameron@huawei.com>
To: "David Hildenbrand (Arm)" <david@kernel.org>
Cc: <linux-kernel@vger.kernel.org>,
	Catalin Marinas <catalin.marinas@arm.com>,
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Subject: Re: [PATCH 0/2] mm: remove CONFIG_ARCH_ENABLE_MEMORY_HOTREMOVE and cleanup CONFIG_MIGRATION
Date: Thu, 19 Mar 2026 11:03:46 +0000	[thread overview]
Message-ID: <20260319110346.000034a5@huawei.com> (raw)
In-Reply-To: <20260319-config_migration-v1-0-42270124966f@kernel.org>

On Thu, 19 Mar 2026 09:19:39 +0100
"David Hildenbrand (Arm)" <david@kernel.org> wrote:

> 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 :)
Seems fine to me, but I agree it always feels a bit like playing with fire.
So more eyes good!

Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>

> 
> 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,