mips,kgdb: kdb low level trap catch and stack trace
The only way the debugger can handle a trap in inside rcu_lock,
notify_die, or atomic_notifier_call_chain without a recursive fault is
to have a low level "first opportunity handler" do_trap_or_bp() handler.
Generally this will be something the vast majority of folks will not
need, but for those who need it, it is added as a kernel .config
option called KGDB_LOW_LEVEL_TRAP.
Also added was a die notification for oops such that kdb can catch an
oops for analysis.
There appeared to be no obvious way to pass the struct pt_regs from
the original exception back to the stack back tracer, so a special
case was added to show_stack() for when kdb is active because you
generally desire to generally look at the back trace of the original
exception.
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/lib/Kconfig.kgdb b/lib/Kconfig.kgdb
index c56ccb4..43cb93f 100644
--- a/lib/Kconfig.kgdb
+++ b/lib/Kconfig.kgdb
@@ -59,7 +59,7 @@
config KGDB_LOW_LEVEL_TRAP
bool "KGDB: Allow debugging with traps in notifiers"
- depends on X86
+ depends on X86 || MIPS
default n
help
This will add an extra call back to kgdb for the breakpoint