I finally decided to write the 33 lines of code and automate my testing somewhat. Now I get a nightly email showing that LogFS is currently bug-free. Well, obviously it cannot be bug-free - what software ever is? - but at least my GC-heavy testcase runs perfectly for 256 iterations.

If anyone wants to set things up as well, have a look here and here. You have to install libunwind first, which probably requires the usual ./configure, make & make install procedure since your distribusion doesn't ship it (mine didn't). Take about 500MB of disk, most of which goes to a copy of the Linux kernel.