diff options
| -rw-r--r-- | Documentation/DocBook/kgdb.tmpl | 17 | ||||
| -rw-r--r-- | kernel/debug/debug_core.c | 16 |
2 files changed, 33 insertions, 0 deletions
diff --git a/Documentation/DocBook/kgdb.tmpl b/Documentation/DocBook/kgdb.tmpl index d71b57fcf11..4ee4ba3509f 100644 --- a/Documentation/DocBook/kgdb.tmpl +++ b/Documentation/DocBook/kgdb.tmpl @@ -362,6 +362,23 @@ </para> </para> </sect1> + <sect1 id="kgdbreboot"> + <title>Run time parameter: kgdbreboot</title> + <para> The kgdbreboot feature allows you to change how the debugger + deals with the reboot notification. You have 3 choices for the + behavior. The default behavior is always set to 0.</para> + <orderedlist> + <listitem><para>echo -1 > /sys/module/debug_core/parameters/kgdbreboot</para> + <para>Ignore the reboot notification entirely.</para> + </listitem> + <listitem><para>echo 0 > /sys/module/debug_core/parameters/kgdbreboot</para> + <para>Send the detach message to any attached debugger client.</para> + </listitem> + <listitem><para>echo 1 > /sys/module/debug_core/parameters/kgdbreboot</para> + <para>Enter the debugger on reboot notify.</para> + </listitem> + </orderedlist> + </sect1> </chapter> <chapter id="usingKDB"> <title>Using kdb</title> diff --git a/kernel/debug/debug_core.c b/kernel/debug/debug_core.c index 3c1ad4e0354..3f88a45e6f0 100644 --- a/kernel/debug/debug_core.c +++ b/kernel/debug/debug_core.c @@ -76,6 +76,8 @@ static int exception_level; struct kgdb_io *dbg_io_ops; static DEFINE_SPINLOCK(kgdb_registration_lock); +/* Action for the reboot notifiter, a global allow kdb to change it */ +static int kgdbreboot; /* kgdb console driver is loaded */ static int kgdb_con_registered; /* determine if kgdb console output should be used */ @@ -97,6 +99,7 @@ static int __init opt_kgdb_con(char *str) early_param("kgdbcon", opt_kgdb_con); module_param(kgdb_use_con, int, 0644); +module_param(kgdbreboot, int, 0644); /* * Holds information about breakpoints in a kernel. These breakpoints are @@ -788,8 +791,21 @@ void __init dbg_late_init(void) static int dbg_notify_reboot(struct notifier_block *this, unsigned long code, void *x) { + /* + * Take the following action on reboot notify depending on value: + * 1 == Enter debugger + * 0 == [the default] detatch debug client + * -1 == Do nothing... and use this until the board resets + */ + switch (kgdbreboot) { + case 1: + kgdb_breakpoint(); + case -1: + goto done; + } if (!dbg_kdb_mode) gdbstub_exit(code); +done: return NOTIFY_DONE; } |