1 files changed, 19 insertions, 0 deletions

diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c
index 868bbde74698..17f518839028 100644
--- a/arch/x86/mm/ioremap.c
+++ b/arch/x86/mm/ioremap.c
@@ -35,6 +35,18 @@ unsigned long __phys_addr(unsigned long x)
 }
 EXPORT_SYMBOL(__phys_addr);
 
+static inline int phys_addr_valid(unsigned long addr)
+{
+        return addr < (1UL << boot_cpu_data.x86_phys_bits);
+}
+
+#else
+
+static inline int phys_addr_valid(unsigned long addr)
+{
+        return 1;
+}
+
 #endif
 
 int page_is_ram(unsigned long pagenr)
@@ -118,6 +130,13 @@ static void __iomem *__ioremap(resource_size_t phys_addr, unsigned long size,
         if (!size || last_addr < phys_addr)
                 return NULL;
 
+        if (!phys_addr_valid(phys_addr)) {
+                printk(KERN_WARNING "ioremap: invalid physical address %lx\n",
+                       phys_addr);
+                WARN_ON_ONCE(1);
+                return NULL;
+        }
+
         /*
          * Don't remap the low PCI/ISA area, it's always mapped..
          */