x86: warn about RAM pages in ioremap()

Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 4 insertions, 2 deletions

diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c
index e5608d380176..3d0a589d92c4 100644
--- a/arch/x86/mm/ioremap.c
+++ b/arch/x86/mm/ioremap.c
@@ -149,9 +149,11 @@ static void __iomem *__ioremap(resource_size_t phys_addr, unsigned long size,
         for (pfn = phys_addr >> PAGE_SHIFT;
                                 (pfn << PAGE_SHIFT) < last_addr; pfn++) {
 
-                if (page_is_ram(pfn) && pfn_valid(pfn) &&
-                    !PageReserved(pfn_to_page(pfn)))
+                int is_ram = page_is_ram(pfn);
+
+                if (is_ram && pfn_valid(pfn) && !PageReserved(pfn_to_page(pfn)))
                         return NULL;
+                WARN_ON_ONCE(is_ram);
         }
 
         switch (mode) {