Re: [PATCH v4 2/5] x86, traps: Track entry into and exit from IST context

Borislav Petkov
2015-01-23T18:05:06Z

On Fri, Jan 23, 2015 at 09:58:01AM -0800, Andy Lutomirski wrote:
> > [ 543.999079] Call Trace:
> > [ 543.999079] dump_stack (lib/dump_stack.c:52)
> > [ 543.999079] lockdep_rcu_suspicious (kernel/locking/lockdep.c:4259)
> > [ 543.999079] atomic_notifier_call_chain (include/linux/rcupdate.h:892 kernel/notifier.c:182 kernel/notifier.c:193)
> > [ 543.999079] ? atomic_notifier_call_chain (kernel/notifier.c:192)
> > [ 543.999079] notify_die (kernel/notifier.c:538)
> > [ 543.999079] ? atomic_notifier_call_chain (kernel/notifier.c:538)
> > [ 543.999079] ? debug_smp_processor_id (lib/smp_processor_id.c:57)
> > [ 543.999079] do_debug (arch/x86/kernel/traps.c:652)
> > [ 543.999079] ? trace_hardirqs_on (kernel/locking/lockdep.c:2609)
> > [ 543.999079] ? do_int3 (arch/x86/kernel/traps.c:610)
> > [ 543.999079] ? trace_hardirqs_on_caller (kernel/locking/lockdep.c:2554 kernel/locking/lockdep.c:2601)
> > [ 543.999079] debug (arch/x86/kernel/entry_64.S:1310)
>
> I don't know how to read this stack trace. Are we in do_int3,
> do_debug, or both? I didn't change do_debug at all.

It looks like we're in do_debug. do_int3 is only on the stack but not
part of the current frame if I can trust the '?' ...

--
Regards/Gruss,
Boris.

ECO tip #101: Trim your mails when you reply.
--