Re: lttv SEGV when ltt-probe-arm loaded

* Mathieu Desnoyers ([email protected]) wrote:
> * Kevin Hilman ([email protected]) wrote:
> > Mathieu Desnoyers wrote:
> > > * Kevin Hilman ([email protected]) wrote:
> > >> I noticed that when I loaded all the ltt-probe* modules and tried to
> > >> view the resulting trace, the viewer crashed.
> > >>
> > >> I tracked it down to the combination of ltt-probe-arm and
> > >> ltt-probe-kernel.   If either are loaded alone, I can view the trace
> > >> fine.  If they are both loaded, lttv-gui segfaults.
> > >>
> > >> Here's the console output, and a tarball of the trace dir is attached.
> > >>
> > >> khilman@paris:~$ lttv-gui -t ~/tmp/trace
> > >> ** Message: event viewer : background computation data ready.
> > >> ** Message: control flow viewer : background computation data ready.
> > >> /usr/local/bin/lttv-gui: line 10: 10944 Segmentation fault
> > >> $LTTV_CMD.real -m guievents -m guifilter -m guicontrolflow -m
> > >> guistatistics -m guitracecontrol $*
> > >>
> > >>
> > >> Kevin
> > > 
> > > Hi,
> > > 
> > > Can you give the versions you use ?
> > 
> > ltt 0.6.26
> > LinuxTraceToolkitViewer-0.8.69-27102006
> > 
> > > On what architecture are you running lttv ?
> > 
> > x86, distro: Ubuntu Edgy.
> > 
> > Target arch: IXP4xx, big-endian XScale
> > 
> 
> A quick debugging shows me that the problem is a segmentation fault in the
> guistatistics module, due to a system call with ID 983045 (quite high!).
> Starting lttv without guistatistics will show the trace, but I will investigate
> further : there seems to be a problem in the system call instrumentation.
> 
> Mathieu
> 

I found the cause :

There are gaps of unused syscall ID in the syscall enum for ARM. I will modify
LTTV so it deals with this.

However, the syscall ID 291 should really be added to kernel_arch_arm.xml.

Mathieu

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