From: Ralf Baechle on
On Fri, Feb 12, 2010 at 04:35:34PM -0600, Jason Wessel wrote:

> 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.
> CC: Ralf Baechle <ralf(a)>
> Signed-off-by: Jason Wessel <jason.wessel(a)>

Acked-by: Ralf Baechle <ralf(a)>

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