diff --git a/util-linux/fdisk.c b/util-linux/fdisk.c
index 02c5c10ff..6c28e02ec 100644
--- a/util-linux/fdisk.c
+++ b/util-linux/fdisk.c
@@ -55,6 +55,11 @@
 #define BLKGETSIZE _IO(0x12,96)    /* return device size */
 #define BLKFLSBUF  _IO(0x12,97)    /* flush buffer cache */
 #define BLKSSZGET  _IO(0x12,104)   /* get block device sector size */
+
+/* Avoid conflicts with the 2.6 kernel headers, which define
+ * _IOR rather differently */ 
+#undef _IOR
+#define _IOR(type,nr,size)      _IOC(_IOC_READ,(type),(nr),sizeof(size))
 #define BLKGETSIZE64 _IOR(0x12,114,8)  /* 8 = sizeof(u64) */
 
 /*