[ltt-dev] Crash in lttv-0.12.12

[Mathieu Desnoyers]

And here is the offending code :

eventhooks.c :

int before_execmode_hook_trap(void *hook_data, void *call_data)


  if (tfc->tf->name != LTT_CHANNEL_KERNEL)
    return 0;
  minfo = marker_get_info_from_id(tfc->tf->mdata, e->event_id);
  g_assert(minfo != NULL);
  if (minfo->name == LTT_EVENT_TRAP_ENTRY
      || minfo->name == LTT_EVENT_PAGE_FAULT_ENTRY
      || minfo->name == LTT_EVENT_PAGE_FAULT_NOSEM_ENTRY) {
    trap = ltt_event_get_long_unsigned(e, lttv_trace_get_hook_field(th, 0));
  } else if (minfo->name == LTT_EVENT_TRAP_EXIT
             || minfo->name == LTT_EVENT_PAGE_FAULT_EXIT
             || minfo->name == LTT_EVENT_PAGE_FAULT_NOSEM_EXIT) {
    trap = ts->cpu_states[cpu].last_trap;
  } else
    return 0;

  guint trace_num = ts->parent.index;

  /* Well, the process_out existed : we must get it in the process hash
   * or add it, and draw its items.
   */
   /* Add process to process list (if not present) */
  guint pl_height = 0;
  HashedResourceData *hashed_process_data = NULL;
  ProcessList *process_list = resourceview_data->process_list;

  hashed_process_data = resourcelist_obtain_trap(resourceview_data, trace_num, trap);

we end up calling resourcelist_obtain_trap() with a trap id of -1.

I bet the trace first has a trap exit event, without any prior trap
entry. Therefore, the last_trap is probably set to -1, which is used as
trap id.

I fixed it in LTTV 0.12.14. It seems to work fine for me now.

I also took care of fixing the irq and softirq code, which has the same
problem.

Mathieu

* Mathieu Desnoyers (compudj at krystal.dyndns.org) wrote:
> Hi Gregory,
> 
> It's a bug in the resource view. I will put Pierre-Marc in CC, since he
> maintains this view.
> 
> Thanks for the report,
> 
> Mathieu
> 
> * Gregory Haskins (gregory.haskins at gmail.com) wrote:
> > Hi Mathieu, ltt-devs,
> > 
> > Found this on lttv-0.12.12 against 30-rc5-0.136 trace data when I try to
> > open the RV.
> > 
> > Program received signal SIGSEGV, Segmentation fault.
> > 0x00007ffff15048a2 in draw_closure ()
> >    from /usr/lib64/lttv/plugins/libresourceview.so
> > Current language:  auto; currently asm
> > (gdb) bt
> > #0  0x00007ffff15048a2 in draw_closure ()
> >    from /usr/lib64/lttv/plugins/libresourceview.so
> > #1  0x00007ffff751de5d in g_hash_table_foreach ()
> >    from /usr/lib64/libglib-2.0.so.0
> > #2  0x00007ffff1507776 in after_chunk ()
> >    from /usr/lib64/lttv/plugins/libresourceview.so
> > #3  0x000000000040db97 in lttv_hooks_call ()
> > #4  0x00007ffff45f7739 in execute_events_requests ()
> >    from /usr/lib64/liblttvwindow.so.0
> > #5  0x00007ffff752c0fb in g_main_context_dispatch ()
> >    from /usr/lib64/libglib-2.0.so.0
> > #6  0x00007ffff752f8cd in ?? () from /usr/lib64/libglib-2.0.so.0
> > #7  0x00007ffff752fdfd in g_main_loop_run () from
> > /usr/lib64/libglib-2.0.so.0
> > #8  0x00007ffff6253a17 in gtk_main () from /usr/lib64/libgtk-x11-2.0.so.0
> > #9  0x00007ffff45f3666 in window_creation_hook ()
> >    from /usr/lib64/liblttvwindow.so.0
> > #10 0x000000000040db97 in lttv_hooks_call ()
> > #11 0x000000000040c3c3 in main ()
> > 
> > I uploaded the trace and coredump here:
> > 
> > ftp://ftp.novell.com/dev/ghaskins/lttv-0.12.12-crash.tar.bz2
> > 
> > and the binary I used can be found here:
> > 
> > http://download.opensuse.org/repositories/home://ghaskins://lttng/openSUSE_11.1/x86_64/lttv-0.12.12-3.1.x86_64.rpm
> > 
> > Note that this seems specific to this particular trace.  RV opens fine
> > for most other traces I try.
> > 
> > Let me know if there is anything I can do to help or provide more info.
> > 
> > -Greg
> > 
> 
> 
> 
> > _______________________________________________
> > ltt-dev mailing list
> > ltt-dev at lists.casi.polymtl.ca
> > http://lists.casi.polymtl.ca/cgi-bin/mailman/listinfo/ltt-dev
> 
> 
> -- 
> Mathieu Desnoyers
> OpenPGP key fingerprint: 8CD5 52C3 8E3C 4140 715F  BA06 3F25 A8FE 3BAE 9A68

-- 
Mathieu Desnoyers
OpenPGP key fingerprint: 8CD5 52C3 8E3C 4140 715F  BA06 3F25 A8FE 3BAE 9A68