path: root/kernel/extable.c
diff options
authorIngo Molnar <>2009-03-20 11:05:04 +0100
committerIngo Molnar <>2009-03-20 11:09:27 +0100
commit505f2b970b2269ce4cb669b3ff4f6479d379cec2 (patch)
tree741b9ed4752d852eb8b01dd4b4be765c9f37015e /kernel/extable.c
parent22de89b371a18086162eacd9f8c960299334ab01 (diff)
tracing, Text Edit Lock - kprobes architecture independent support, nommu fix
Impact: build fix on SH !CONFIG_MMU Stephen Rothwell reported this linux-next build failure on the SH architecture: kernel/built-in.o: In function `disable_all_kprobes': kernel/kprobes.c:1382: undefined reference to `text_mutex' [...] And observed: | Introduced by commit 4460fdad85becd569f11501ad5b91814814335ff ("tracing, | Text Edit Lock - kprobes architecture independent support") from the | tracing tree. text_mutex is defined in mm/memory.c which is only built | if CONFIG_MMU is defined, which is not true for sh allmodconfig. Move this lock to kernel/extable.c (which is already home to various kernel text related routines), which file is always built-in. Reported-by: Stephen Rothwell <> Cc: Paul Mundt <> Cc: Mathieu Desnoyers <> LKML-Reference: <> Signed-off-by: Ingo Molnar <>
Diffstat (limited to 'kernel/extable.c')
1 files changed, 12 insertions, 2 deletions
diff --git a/kernel/extable.c b/kernel/extable.c
index 0df6253730be..25d39b0c3a1b 100644
--- a/kernel/extable.c
+++ b/kernel/extable.c
@@ -15,11 +15,21 @@
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+#include <linux/ftrace.h>
#include <linux/module.h>
+#include <linux/mutex.h>
#include <linux/init.h>
-#include <linux/ftrace.h>
-#include <asm/uaccess.h>
#include <asm/sections.h>
+#include <asm/uaccess.h>
+ * mutex protecting text section modification (dynamic code patching).
+ * some users need to sleep (allocating memory...) while they hold this lock.
+ *
+ * NOT exported to modules - patching kernel text is a really delicate matter.
+ */
extern struct exception_table_entry __start___ex_table[];
extern struct exception_table_entry __stop___ex_table[];