[PATCH-stable] powerpc: Fix incorrect setting of __HAVE_ARCH_PTE_SPECIAL

[Benjamin Herrenschmidt]

From: Weirich, Bernhard <Bernhard.Weirich at riedel.net>

The test that decides whether to define __HAVE_ARCH_PTE_SPECIAL on
powerpc is bogus and will end up always defining it, even when
_PAGE_SPECIAL is not supported (in which case it's 0) such as on
8xx or 40x processors.

Signed-off-by: Bernhard Weirich <bernhard.weirich at riedel.net>
Signed-off-by: Benjamin Herrenschmidt <benh at kernel.crashing.org>
---
 arch/powerpc/include/asm/pte-common.h |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

Greg: I'm going to fix upstream differently, by having all CPU types
actually support _PAGE_SPECIAL, but I prefer the simple and obvious
fix for -stable.

This should apply to v2.6.30 and v2.6.31


diff --git a/arch/powerpc/include/asm/pte-common.h b/arch/powerpc/include/asm/pte-common.h
index a7e210b..0cd2e34 100644
--- a/arch/powerpc/include/asm/pte-common.h
+++ b/arch/powerpc/include/asm/pte-common.h
@@ -176,7 +176,7 @@ extern unsigned long bad_call_to_PMD_PAGE_SIZE(void);
 #define HAVE_PAGE_AGP
 
 /* Advertise support for _PAGE_SPECIAL */
-#ifdef _PAGE_SPECIAL
+#if _PAGE_SPECIAL != 0
 #define __HAVE_ARCH_PTE_SPECIAL
 #endif