Re: [PATCH] acpi/hmat,mm/memtier: always register hmat adist calculation callback

From: Gregory Price
Date: Tue Aug 27 2024 - 10:33:49 EST


On Wed, Jul 31, 2024 at 09:22:32AM +0800, Huang, Ying wrote:
> >
> > This presumes driver configured devices, which is not always the case.
> >
> > kmem.c will set MEMTIER_DEFAULT_DAX_ADISTANCE
> >
> > but if BIOS/EFI has set up the node instead, you get the default of
> > MEMTIER_ADISTANCE_DRAM if HMAT is not present or otherwise not sane.
>
> "efi_fake_mem=" kernel parameter can be used to add "EFI_MEMORY_SP" flag
> to the memory range, so that kmem.c can manage it.
>

Worth noting: This feature was removed
https://lore.kernel.org/all/20240620073205.1543145-1-ardb+git@xxxxxxxxxx/

So I cannot even use this to manage it.

~Gregory