Re: [PATCH 1/2] mm: remove CONFIG_ARCH_ENABLE_MEMORY_HOTREMOVE

From: Mike Rapoport <rppt@kernel.org>
To: "David Hildenbrand (Arm)" <david@kernel.org>
Cc: linux-kernel@vger.kernel.org,
	Catalin Marinas <catalin.marinas@arm.com>,
	Will Deacon <will@kernel.org>,
	Huacai Chen <chenhuacai@kernel.org>,
	WANG Xuerui <kernel@xen0n.name>,
	Madhavan Srinivasan <maddy@linux.ibm.com>,
	Michael Ellerman <mpe@ellerman.id.au>,
	Nicholas Piggin <npiggin@gmail.com>,
	"Christophe Leroy (CS GROUP)" <chleroy@kernel.org>,
	Paul Walmsley <pjw@kernel.org>,
	Palmer Dabbelt <palmer@dabbelt.com>,
	Albert Ou <aou@eecs.berkeley.edu>,
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Subject: Re: [PATCH 1/2] mm: remove CONFIG_ARCH_ENABLE_MEMORY_HOTREMOVE
Date: Thu, 19 Mar 2026 18:18:22 +0200	[thread overview]
Message-ID: <abwhzkhM9Bk9xPIf@kernel.org> (raw)
In-Reply-To: <20260319-config_migration-v1-1-42270124966f@kernel.org>

On Thu, Mar 19, 2026 at 09:19:40AM +0100, David Hildenbrand (Arm) wrote:
> All architectures that select CONFIG_ARCH_ENABLE_MEMORY_HOTREMOVE also
> select CONFIG_ARCH_ENABLE_MEMORY_HOTPLUG. So we can just remove
> CONFIG_ARCH_ENABLE_MEMORY_HOTREMOVE.
> 
> For CONFIG_MIGRATION, make it depend on CONFIG_MEMORY_HOTREMOVE instead,
> and make CONFIG_MEMORY_HOTREMOVE select CONFIG_MIGRATION (just like
> CONFIG_CMA and CONFIG_COMPACTION already do).
> 
> We'll clean up CONFIG_MIGRATION next.
> 
> Signed-off-by: David Hildenbrand (Arm) <david@kernel.org>

Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org>

> ---
>  arch/arm64/Kconfig     | 1 -
>  arch/loongarch/Kconfig | 1 -
>  arch/powerpc/Kconfig   | 1 -
>  arch/riscv/Kconfig     | 1 -
>  arch/s390/Kconfig      | 1 -
>  arch/x86/Kconfig       | 1 -
>  mm/Kconfig             | 9 +++------
>  7 files changed, 3 insertions(+), 12 deletions(-)
> 
> diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
> index edc927d9e85a..d01800962d84 100644
> --- a/arch/s390/Kconfig
> +++ b/arch/s390/Kconfig
> @@ -85,7 +85,6 @@ config S390
>  	select ARCH_32BIT_USTAT_F_TINODE
>  	select ARCH_CORRECT_STACKTRACE_ON_KRETPROBE
>  	select ARCH_ENABLE_MEMORY_HOTPLUG if SPARSEMEM

Not really related, but s390 does not have anything but SPARSEMEM_VMEMMAP.

> -	select ARCH_ENABLE_MEMORY_HOTREMOVE
>  	select ARCH_ENABLE_SPLIT_PMD_PTLOCK if PGTABLE_LEVELS > 2
>  	select ARCH_ENABLE_THP_MIGRATION if TRANSPARENT_HUGEPAGE
>  	select ARCH_HAS_CC_CAN_LINK

-- 
Sincerely yours,
Mike.