Re: [PATCH] mm/Kconfig: allow user to select MIGRATION if MEMORY_FAILURE is enabled

[Mike Rapoport <rppt@kernel.org>]

On Wed, Aug 12, 2026 at 11:55:03AM +0100, Lorenzo Stoakes (ARM) wrote:
> On Wed, Aug 12, 2026 at 01:45:30PM +0300, Mike Rapoport wrote:
> > Hi,
> >
> > On Wed, Aug 12, 2026 at 05:16:44PM +0800, Xie Yuanbin wrote:
> > > Currently, memory-failure can be enabled without migration. However,
> > > migration cannot be selected by user when memory-failure is enabled.
> > >
> > > Migration is very useful for soft_offline_page(), which may be triggered
> > > by correctable memory errors. Most of the anonymous or file-mapping
> > > faulty pages can be migrated to other healthy pages.
> > >
> > > Allow user to select MIGRATION if MEMORY_FAILURE is enabled.
> > > Also, select MIGRATION by default if MEMORY_FAILURE is enabled.
> >
> > Do we want to make users decide if they need MIGRATION when MEMORY_FAILURE
> > is enabled?
> >
> > Just make MEMORY_FAILURE select MIGRATION.
> 
> NO.
> 
> Explain first why the hell one of the other options that selection migration
> can't be enabled.

Think small systems ;-P
 
> Changing configs just to support a weirdo no to compaction but yes to doing soft
> offline for debugging or whatever isn't really convincing unless a real world,
> sensible use case can be stated.
> 
> The kernel isn't there to allow you to have broken configs.
> 
> >
> > > Signed-off-by: Xie Yuanbin <xieyuanbin1@huawei.com>
> > > ---
> > >  mm/Kconfig | 3 ++-
> > >  1 file changed, 2 insertions(+), 1 deletion(-)
> > >
> > > diff --git a/mm/Kconfig b/mm/Kconfig
> > > index 8a24c130d008..b4c217383b51 100644
> > > --- a/mm/Kconfig
> > > +++ b/mm/Kconfig
> > > @@ -682,7 +682,8 @@ config NUMA_MIGRATION
> > >  	  demotion for memory tiering.
> > >
> > >  config MIGRATION
> > > -	bool
> > > +	bool "Enable page migration" if MEMORY_FAILURE
> > > +	default y if MEMORY_FAILURE
> > >  	depends on MMU
> > >
> > >  config DEVICE_MIGRATION
> > > --
> > > 2.55.0
> > >
> >
> > --
> > Sincerely yours,
> > Mike.
> 
> --
> Cheers, Lorenzo

-- 
Sincerely yours,
Mike.