From 4402c153cb9c549cd21d6007ef0dfac50c8d148d Mon Sep 17 00:00:00 2001 From: Jason Wessel Date: Thu, 20 May 2010 21:04:28 -0500 Subject: [PATCH] kdb,debug_core: Allow the debug core to receive a panic notification 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 CC: Andrew Morton CC: Eric W. Biederman Signed-off-by: Jason Wessel --- kernel/debug/debug_core.c | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) diff --git a/kernel/debug/debug_core.c b/kernel/debug/debug_core.c index b38bb25dbbb3..64b5588c9638 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); -- 2.30.2