1 files changed, 29 insertions, 3 deletions

diff --git a/kernel/debug/debug_core.c b/kernel/debug/debug_core.c
index 0557f24c6bca..9a61738cefc8 100644
--- a/kernel/debug/debug_core.c
+++ b/kernel/debug/debug_core.c
@@ -672,6 +672,10 @@ kgdb_handle_exception(int evector, int signo, int ecode, struct pt_regs *regs)
 {
         struct kgdb_state kgdb_var;
         struct kgdb_state *ks = &kgdb_var;
+        int ret = 0;
+
+        if (arch_kgdb_ops.enable_nmi)
+                arch_kgdb_ops.enable_nmi(0);
 
         ks->cpu                 = raw_smp_processor_id();
         ks->ex_vector           = evector;
@@ -681,13 +685,33 @@ kgdb_handle_exception(int evector, int signo, int ecode, struct pt_regs *regs)
         ks->linux_regs          = regs;
 
         if (kgdb_reenter_check(ks))
-                return 0; /* Ouch, double exception ! */
+                goto out; /* Ouch, double exception ! */
         if (kgdb_info[ks->cpu].enter_kgdb != 0)
-                return 0;
+                goto out;
 
-        return kgdb_cpu_enter(ks, regs, DCPU_WANT_MASTER);
+        ret = kgdb_cpu_enter(ks, regs, DCPU_WANT_MASTER);
+out:
+        if (arch_kgdb_ops.enable_nmi)
+                arch_kgdb_ops.enable_nmi(1);
+        return ret;
 }
 
+/*
+ * GDB places a breakpoint at this function to know dynamically
+ * loaded objects. It's not defined static so that only one instance with this
+ * name exists in the kernel.
+ */
+
+static int module_event(struct notifier_block *self, unsigned long val,
+        void *data)
+{
+        return 0;
+}
+
+static struct notifier_block dbg_module_load_nb = {
+        .notifier_call  = module_event,
+};
+
 int kgdb_nmicallback(int cpu, void *regs)
 {
 #ifdef CONFIG_SMP
@@ -816,6 +840,7 @@ static void kgdb_register_callbacks(void)
                 kgdb_arch_init();
                 if (!dbg_is_early)
                         kgdb_arch_late();
+                register_module_notifier(&dbg_module_load_nb);
                 register_reboot_notifier(&dbg_reboot_notifier);
                 atomic_notifier_chain_register(&panic_notifier_list,
                                                &kgdb_panic_event_nb);
@@ -839,6 +864,7 @@ static void kgdb_unregister_callbacks(void)
         if (kgdb_io_module_registered) {
                 kgdb_io_module_registered = 0;
                 unregister_reboot_notifier(&dbg_reboot_notifier);
+                unregister_module_notifier(&dbg_module_load_nb);
                 atomic_notifier_chain_unregister(&panic_notifier_list,
                                                &kgdb_panic_event_nb);
                 kgdb_arch_exit();