There's no reason to enable split page table lock if don't have page
tables.

It also triggers build error at least on ARM since we don't define
pmd_page() for !MMU.

In file included from arch/arm/kernel/asm-offsets.c:14:0:
include/linux/mm.h: In function 'pte_lockptr':
include/linux/mm.h:1392:2: error: implicit declaration of function 'pmd_page' [-Werror=implicit-function-declaration]
include/linux/mm.h:1392:2: warning: passing argument 1 of 'ptlock_ptr' makes pointer from integer without a cast [enabled by default]
include/linux/mm.h:1384:27: note: expected 'struct page *' but argument is of type 'int'

Reported-by: Uwe Kleine-K??nig <redacted>
Signed-off-by: Kirill A. Shutemov <redacted>
---
 mm/Kconfig | 1 +
 1 file changed, 1 insertion(+)

diff --git a/mm/Kconfig b/mm/Kconfig
index 2d9f1504d75e..90bd85ea6035 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig

@@ -216,6 +216,7 @@ config PAGEFLAGS_EXTENDED
 #
 config SPLIT_PTLOCK_CPUS
 	int
+	default "999999" if !MMU
 	default "999999" if ARM && !CPU_CACHE_VIPT
 	default "999999" if PARISC && !PA20
 	default "4"

-- 
1.9.0