Re: [PATCH v4 1/6] mm, x86: Add ARCH_HAS_ZONE_DEVICE to Kconfig

[Michael Ellerman]

Oliver O'Halloran  writes:

> Currently ZONE_DEVICE depends on X86_64 and this will get unwieldly as
> new architectures (and platforms) get ZONE_DEVICE support. Move to an
> arch selected Kconfig option to save us the trouble.
>
> Cc: linux...@kvack.org
> Acked-by: Ingo Molnar 
> Acked-by: Balbir Singh 
> Signed-off-by: Oliver O'Halloran 
> ---
> Andew, the rest of the series should be going in via the ppc tree, but
> since there's nothing ppc specific about this patch do you want to
> take it via mm?

Except without this patch none of the rest of the series can be tested
on powerpc, because the code doesn't go live until ARCH_HAS_ZONE_DEVICE
is wired up for powerpc.

So it'd be better if the series stayed together, wherever it goes. I'll
pick it up unless Andrew objects.

cheers

[PATCH v4 1/6] mm, x86: Add ARCH_HAS_ZONE_DEVICE to Kconfig

[Oliver O'Halloran]

Currently ZONE_DEVICE depends on X86_64 and this will get unwieldly as
new architectures (and platforms) get ZONE_DEVICE support. Move to an
arch selected Kconfig option to save us the trouble.

Cc: linux...@kvack.org
Acked-by: Ingo Molnar 
Acked-by: Balbir Singh 
Signed-off-by: Oliver O'Halloran 
---
Andew, the rest of the series should be going in via the ppc tree, but
since there's nothing ppc specific about this patch do you want to
take it via mm?
--
v2: Added missing hunk.
---
 arch/x86/Kconfig | 1 +
 mm/Kconfig   | 6 +-
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 37a14d7a4e3f..569e39a8293d 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -61,6 +61,7 @@ config X86
select ARCH_HAS_STRICT_KERNEL_RWX
select ARCH_HAS_STRICT_MODULE_RWX
select ARCH_HAS_UBSAN_SANITIZE_ALL
+   select ARCH_HAS_ZONE_DEVICE if X86_64
select ARCH_HAVE_NMI_SAFE_CMPXCHG
select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI
select ARCH_MIGHT_HAVE_PC_PARPORT
diff --git a/mm/Kconfig b/mm/Kconfig
index 5027cbc251f9..48b1af447fa7 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -668,12 +668,16 @@ config IDLE_PAGE_TRACKING
 
  See Documentation/vm/idle_page_tracking.txt for more details.
 
+# arch_add_memory() comprehends device memory
+config ARCH_HAS_ZONE_DEVICE
+   bool
+
 config ZONE_DEVICE
bool "Device memory (pmem, etc...) hotplug support"
depends on MEMORY_HOTPLUG
depends on MEMORY_HOTREMOVE
depends on SPARSEMEM_VMEMMAP
-   depends on X86_64 #arch_add_memory() comprehends device memory
+   depends on ARCH_HAS_ZONE_DEVICE
 
help
  Device memory hotplug support allows for establishing pmem,
-- 
2.9.4