[RFC] [PATCH 2.6.37-rc5-tip 16/20] 16: uprobes: register a notifier for uprobes.

[Srikar Dronamraju <srikar@linux.vnet.ibm.com>]

Uprobe needs to be intimated on int3 and singlestep exceptions.
Hence uprobes registers a die notifier so that its notified of the events.

Signed-off-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
---
 kernel/uprobes.c |   19 +++++++++++++++++++
 1 files changed, 19 insertions(+), 0 deletions(-)

diff --git a/kernel/uprobes.c b/kernel/uprobes.c
index 3d21d8f..93a3118 100644
--- a/kernel/uprobes.c
+++ b/kernel/uprobes.c
@@ -34,6 +34,7 @@
 #include <linux/rmap.h> /* needed for anon_vma_prepare */
 #include <linux/mman.h>	/* needed for PROT_EXEC, MAP_PRIVATE */
 #include <linux/file.h> /* needed for fput() */
+#include <linux/kdebug.h> /* needed for notifier mechanism */
 
 #define UINSNS_PER_PAGE	(PAGE_SIZE/UPROBES_XOL_SLOT_BYTES)
 #define MAX_UPROBES_XOL_SLOTS UINSNS_PER_PAGE
@@ -1170,3 +1171,21 @@ int uprobe_post_notifier(struct pt_regs *regs)
 	}
 	return 0;
 }
+
+struct notifier_block uprobes_exception_nb = {
+	.notifier_call = uprobes_exception_notify,
+	.priority = 0x7ffffff0,
+};
+
+static int __init init_uprobes(void)
+{
+	register_die_notifier(&uprobes_exception_nb);
+	return 0;
+}
+
+static void __exit exit_uprobes(void)
+{
+}
+
+module_init(init_uprobes);
+module_exit(exit_uprobes);