Re: [PATCH] mm/memory-failure: not select MEMORY_ISOLATION

[Anshuman Khandual <anshuman.khandual@arm.com>]

On 22/09/25 8:06 PM, Xie Yuanbin wrote:
> We added that "select MEMORY_ISOLATION" in commit ee6f509c3274 ("mm:
> factor out memory isolate functions").
> However, in commit add05cecef80 ("mm: soft-offline: don't free target
> page in successful page migration") we remove the need for it,
> where we removed the calls to set_migratetype_isolate() etc.
> 
> What CONFIG_MEMORY_FAILURE soft-offline support wants is migrate_pages()
> support. But that comes with CONFIG_MIGRATION.
> And isolate_folio_to_list() has nothing to do with CONFIG_MEMORY_ISOLATION.
> 
> Therefore, we can remove "select MEMORY_ISOLATION" of MEMORY_FAILURE.
> 
> Acked-by: David Hildenbrand <david@redhat.com>
> Signed-off-by: Xie Yuanbin <xieyuanbin1@huawei.com>
> ---
>  mm/Kconfig | 1 -
>  1 file changed, 1 deletion(-)
> 
> diff --git a/mm/Kconfig b/mm/Kconfig
> index 034a1662d8c1..0e26f4fc8717 100644
> --- a/mm/Kconfig
> +++ b/mm/Kconfig
> @@ -742,21 +742,20 @@ config DEFAULT_MMAP_MIN_ADDR
>  	  This value can be changed after boot using the
>  	  /proc/sys/vm/mmap_min_addr tunable.
>  
>  config ARCH_SUPPORTS_MEMORY_FAILURE
>  	bool
>  
>  config MEMORY_FAILURE
>  	depends on MMU
>  	depends on ARCH_SUPPORTS_MEMORY_FAILURE
>  	bool "Enable recovery from hardware memory errors"
> -	select MEMORY_ISOLATION
>  	select RAS
>  	help
>  	  Enables code to recover from some memory failures on systems
>  	  with MCA recovery. This allows a system to continue running
>  	  even when some of its memory has uncorrected errors. This requires
>  	  special hardware support and typically ECC memory.
>  
>  config HWPOISON_INJECT
>  	tristate "HWPoison pages injector"
>  	depends on MEMORY_FAILURE && DEBUG_KERNEL && PROC_FS

MEMORY_FAILURE does not need MEMORY_ISOLATION to be selected
(and built) in order to be built independently.

Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>