How to debug broken unwinding?

2017-06-01 Thread Milian Wolff
Hey all, on my ArchLinux box I regularly see cases where libdw fails to unwind properly. I can reproduce this both with upstream perf as well as with the perfparser utility. How should I debug this, or how can I report a good bug report for this? I guess I could upload a perf archive and docum

overflows in Dwfl_Thread_Callbacks::memory_read callback

2017-06-01 Thread Milian Wolff
Hey all, in the perfparser that Ulf wrote, and to which I'm contributing too, we often see abnormal data being passed to the memory_read callback we define. I.e. our callback gets invoked with addr=0x which clearly isn't an expected or valid address. So far we ignored this, as