powerpc: Fix pfn_valid() when memory starts at a non-zero address
max_mapnr is a pfn, not an index innto mem_map[]. So don't add
ARCH_PFN_OFFSET a second time.
Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
diff --git a/arch/powerpc/include/asm/page.h b/arch/powerpc/include/asm/page.h
index 53b64be..da4b200 100644
--- a/arch/powerpc/include/asm/page.h
+++ b/arch/powerpc/include/asm/page.h
@@ -101,7 +101,7 @@
#ifdef CONFIG_FLATMEM
#define ARCH_PFN_OFFSET (MEMORY_START >> PAGE_SHIFT)
-#define pfn_valid(pfn) ((pfn) >= ARCH_PFN_OFFSET && (pfn) < (ARCH_PFN_OFFSET + max_mapnr))
+#define pfn_valid(pfn) ((pfn) >= ARCH_PFN_OFFSET && (pfn) < max_mapnr)
#endif
#define virt_to_page(kaddr) pfn_to_page(__pa(kaddr) >> PAGE_SHIFT)