svn commit: r283254 - head/sys/sys

[Dimitry Andric]

Author: dim
Date: Thu May 21 17:40:53 2015
New Revision: 283254
URL: https://svnweb.freebsd.org/changeset/base/283254

Log:
  Ensure that the static structs emitted by the MODULE_DEPEND() and
  MODULE_VERSION() macros don't end up as .comm symbols, when all the
  version fields are zero.
  
  Normally, such symbols will end up in .bss, but for kernel module
  version objects, this can lead to "garbage" version numbers.
  
  Fix this by instructing the compiler to always put these structs in the
  .data segment instead.
  
  Reported by:	delphij, ae
  MFC after:	1 week

Modified:
  head/sys/sys/module.h

Modified: head/sys/sys/module.h
==============================================================================
--- head/sys/sys/module.h	Thu May 21 17:39:42 2015	(r283253)
+++ head/sys/sys/module.h	Thu May 21 17:40:53 2015	(r283254)
@@ -107,7 +107,8 @@ struct mod_metadata {
 	DATA_SET(modmetadata_set, _mod_metadata##uniquifier)
 
 #define	MODULE_DEPEND(module, mdepend, vmin, vpref, vmax)		\
-	static struct mod_depend _##module##_depend_on_##mdepend = {	\
+	static struct mod_depend _##module##_depend_on_##mdepend	\
+	    __section(".data") = {					\
 		vmin,							\
 		vpref,							\
 		vmax							\
@@ -147,7 +148,8 @@ struct mod_metadata {
 	DECLARE_MODULE_WITH_MAXVER(name, data, sub, order, __FreeBSD_version)
 
 #define	MODULE_VERSION(module, version)					\
-	static struct mod_version _##module##_version = {		\
+	static struct mod_version _##module##_version			\
+	    __section(".data") = {					\
 		version							\
 	};								\
 	MODULE_METADATA(_##module##_version, MDT_VERSION,		\