Monthly Archives: October 2010

Getting the backtrace from a kernel panic

You may know the following situation. You arrive in the morning in the office, do what you always do and check out the latest changes of the software you are working on. After a little bit of compile time and the first coffee you start the just build application. Bumm, kernel panic. After rebooting and locking through the changes you may have an idea what the reason for this could be. A colleague of you is working on a fancy new feature which needed changes to a kernel module. As you almost know nothing about this code you seek for help and, as it of course not happen on his computer, he is asking for a backtrace of this panic. You have two problems now. First you need to see the panic yourself and second it would be nice to get a copy of the backtrace for sharing this info within a bugtracker. In the following post I will show how both aims could be easily archived.


Using suppression files with Valgrind

Valgrind is one of the great tools in the long list of freely available applications for development. Beside several profiling tools it also contains a memory checker. Leaking memory is one of the more common errors a programmer could step into. Basically it means to forget freeing memory (or in a more general sense: any resource) a program has acquired. If you are a perfect developer, this will never happen to you. If you are a good developer it may happen and that’s where Valgrind will save you some trouble. As most of the developers out there are more or less good developers, their programs produce memory leaks, too ;). The right solution for this, is of course to write a bug report. But there are times where this isn’t possible or you are in hurry and don’t want to see all the errors of a third-party library you link against.