It is highly desirable to trap into kdb on panic. The debug core will
attempt to register as the first in line for the panic notifier.
CC: Ingo Molnar <mi...@elte.hu>
CC: Andrew Morton <a...@linux-foundation.org>
CC: Eric W. Biederman <ebied...@xmission.com>
Signed-off-by: Jason Wessel <jason.wes...@windriver.com>
---
kernel/debug/debug_core.c | 19 +++++++++++++++++++
1 files changed, 19 insertions(+), 0 deletions(-)
diff --git a/kernel/debug/debug_core.c b/kernel/debug/debug_core.c
index b38bb25..64b5588 100644
--- a/kernel/debug/debug_core.c
+++ b/kernel/debug/debug_core.c
@@ -762,11 +762,28 @@ static struct sysrq_key_op sysrq_dbg_op = {
};
#endif
+static int kgdb_panic_event(struct notifier_block *self,
+ unsigned long val,
+ void *data)
+{
+ if (dbg_kdb_mode)
+ kdb_printf("PANIC: %s\n", (char *)data);
+ kgdb_breakpoint();
+ return NOTIFY_DONE;
+}
+
+static struct notifier_block kgdb_panic_event_nb = {
+ .notifier_call = kgdb_panic_event,
+ .priority = INT_MAX,
+};
+
static void kgdb_register_callbacks(void)
{
if (!kgdb_io_module_registered) {
kgdb_io_module_registered = 1;
kgdb_arch_init();
+ atomic_notifier_chain_register(&panic_notifier_list,
+ &kgdb_panic_event_nb);
#ifdef CONFIG_MAGIC_SYSRQ
register_sysrq_key('g', &sysrq_dbg_op);
#endif
@@ -786,6 +803,8 @@ static void kgdb_unregister_callbacks(void)
*/
if (kgdb_io_module_registered) {
kgdb_io_module_registered = 0;
+ atomic_notifier_chain_unregister(&panic_notifier_list,
+ &kgdb_panic_event_nb);
kgdb_arch_exit();
#ifdef CONFIG_MAGIC_SYSRQ
unregister_sysrq_key('g', &sysrq_dbg_op);
--
1.6.3.3
------------------------------------------------------------------------------
_______________________________________________
Kgdb-bugreport mailing list
Kgdb-bugreport@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/kgdb-bugreport
