diff --git a/arch/ia64/include/asm/io.h b/arch/ia64/include/asm/io.h
index 6f952171abf9458ab9777566cb7647e1e03217df..1e6fef69bb01c26286df9ea7963d092b442e66ab 100644
--- a/arch/ia64/include/asm/io.h
+++ b/arch/ia64/include/asm/io.h
@@ -454,6 +454,7 @@ extern void memset_io(volatile void __iomem *s, int c, long n);
 #define xlate_dev_kmem_ptr xlate_dev_kmem_ptr
 #define xlate_dev_mem_ptr xlate_dev_mem_ptr
 #include <asm-generic/io.h>
+#undef PCI_IOBASE
 
 # endif /* __KERNEL__ */