[PATCH 1/1] Fix segfault in DTC

[David Gibson]

On Sun, Sep 30, 2012 at 11:34:50PM -0600, Stephen Warren wrote:
> On 09/29/2012 05:53 PM, David Gibson wrote:
> > On Fri, Sep 28, 2012 at 01:05:33PM -0600, Stephen Warren wrote:
> >> On 09/28/2012 12:53 PM, Jon Loeliger wrote:
> >>>>>
> >>>>> Yeah, seems like the kernel DTC is quite old.
> >>>>
> >>>> FYI, I'm working on a patch to the kernel to bring in the latest dtc.
> >>>
> >>> Awesome.  Thank you.
> >>>
> >>>> I've run a regression test vs. the old dtc in the kernel ...
> >>>
> >>> Which is the icky step.  Again, thank you.
> >>>
> >>>> ... and found that
> >>>> some of the PowerPC .dts files don't compile with the new dtc (but did
> >>>> with the old), all due to non-existent labels/paths being referenced.
> >>>> I'll try and track down whether this is a regression in dtc, or simply
> >>>> buggy .dts files that weren't noticed before.
> >>>
> >>> I think you should just smack the PowerPC guys. :-)
> >>
> >> For the record in this thread, it was a regression I introduced into dtc
> >> - the patch I just sent was for this.
> > 
> > I would be nice to add a testcase for this regression into dtc.
> 
> The issue here was caused by uninitialized memory, so it would, I think,
> be basically impossible to create a test-case that would be guaranteed
> to fail because of this; it'd depend on the internal details of the
> malloc library and how/when it re-used previously free()d memory blocks.

It doesn't have to be guaranteed to fail to be useful.  Plus, we
already have the infrastructure to run the tests under valgrind, which
would catch it.

-- 
David Gibson			| I'll have my music baroque, and my code
david AT gibson.dropbear.id.au	| minimalist, thank you.  NOT _the_ _other_
				| _way_ _around_!
http://www.ozlabs.org/~dgibson