[RFC PATCH] PPC32: Fix build failure caused by missing dirty pte handlers

[Pranith Kumar <bobby.prani@gmail.com>]

In 4.5-rc1, I am getting a build failure as follows:

mm/memory.c: In function ‘do_swap_page’:
mm/memory.c:2573:9: error: implicit declaration of function ‘pte_mksoft_dirty’
[-Werror=implicit-function-declaration]
   pte = pte_mksoft_dirty(pte);

The soft dirty pte handlers are declared only for PPC64 on PPC_BOOK3S in
arch/powerpc/include/asm/book3s/64/hash.h and missing in the 32-bit arch.

Avoid this error by not setting HAVE_ARCH_SOFT_DIRTY for 32-bit system.

Signed-off-by: Pranith Kumar <bobby.prani@gmail.com>
---
 arch/powerpc/Kconfig | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index e4824fd..21cb5c5 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -557,7 +557,7 @@ choice
 
 config PPC_4K_PAGES
 	bool "4k page size"
-	select HAVE_ARCH_SOFT_DIRTY if CHECKPOINT_RESTORE && PPC_BOOK3S
+	select HAVE_ARCH_SOFT_DIRTY if CHECKPOINT_RESTORE && PPC_BOOK3S && PPC64
 
 config PPC_16K_PAGES
 	bool "16k page size"
@@ -566,7 +566,7 @@ config PPC_16K_PAGES
 config PPC_64K_PAGES
 	bool "64k page size"
 	depends on !PPC_FSL_BOOK3E && (44x || PPC_STD_MMU_64 || PPC_BOOK3E_64)
-	select HAVE_ARCH_SOFT_DIRTY if CHECKPOINT_RESTORE && PPC_BOOK3S
+	select HAVE_ARCH_SOFT_DIRTY if CHECKPOINT_RESTORE && PPC_BOOK3S && PPC64
 
 config PPC_256K_PAGES
 	bool "256k page size"
-- 
2.7.0