diff -Nrup linux-2.6.19.1/arch/x86_64/kernel/ioport.c linux-2.6.19.1-devel/arch/x86_64/kernel/ioport.c
--- linux-2.6.19.1/arch/x86_64/kernel/ioport.c	2006-12-11 17:32:53.000000000 -0200
+++ linux-2.6.19.1-devel/arch/x86_64/kernel/ioport.c	2007-01-04 07:44:46.000000000 -0200
@@ -114,6 +114,6 @@ asmlinkage long sys_iopl(unsigned int le
 		if (!capable(CAP_SYS_RAWIO))
 			return -EPERM;
 	}
-	regs->eflags = (regs->eflags &~ 0x3000UL) | (level << 12);
+	regs->eflags = (regs->eflags &~ X86_EFLAGS_IOPL) | (level << 12);
 	return 0;
 }