debug: prevent entering debug mode on panic/exception.

[cascardo/linux.git] / kernel / debug / debug_core.c

diff --git a/kernel/debug/debug_core.c b/kernel/debug/debug_core.c
index 07ce18c..0874e2e 100644 (file)
--- a/kernel/debug/debug_core.c
+++ b/kernel/debug/debug_core.c
@@ -604,7 +604,7 @@ return_normal:
                   online_cpus)
                cpu_relax();
        if (!time_left)
-               pr_crit("KGDB: Timed out waiting for secondary CPUs.\n");
+               pr_crit("Timed out waiting for secondary CPUs.\n");
 
        /*
         * At this point the primary processor is completely
@@ -696,6 +696,14 @@ kgdb_handle_exception(int evector, int signo, int ecode, struct pt_regs *regs)
 
        if (arch_kgdb_ops.enable_nmi)
                arch_kgdb_ops.enable_nmi(0);
+       /*
+        * Avoid entering the debugger if we were triggered due to an oops
+        * but panic_timeout indicates the system should automatically
+        * reboot on panic. We don't want to get stuck waiting for input
+        * on such systems, especially if its "just" an oops.
+        */
+       if (signo != SIGTRAP && panic_timeout)
+               return 1;
 
        memset(ks, 0, sizeof(struct kgdb_state));
        ks->cpu                 = raw_smp_processor_id();
@@ -828,6 +836,15 @@ static int kgdb_panic_event(struct notifier_block *self,
                            unsigned long val,
                            void *data)
 {
+       /*
+        * Avoid entering the debugger if we were triggered due to a panic
+        * We don't want to get stuck waiting for input from user in such case.
+        * panic_timeout indicates the system should automatically
+        * reboot on panic.
+        */
+       if (panic_timeout)
+               return NOTIFY_DONE;
+
        if (dbg_kdb_mode)
                kdb_printf("PANIC: %s\n", (char *)data);
        kgdb_breakpoint();