* Stefan Hajnoczi via Gdb: > The QEMU emulator uses coroutines with separate stacks. It can be > challenging to debug coroutines that have yielded because GDB is not > aware of them (no thread is currently executing them). > > QEMU has a GDB Python script that helps. It "creates" a stack frame for > a given coroutine by temporarily setting register values and then using > the "bt" command. This works on a live process under ptrace control but > not for coredumps where registers can't be set. > > Here is the script (or see the bottom of this email for an inline copy > of the relevant code): > https://gitlab.com/qemu-project/qemu/-/blob/master/scripts/qemugdb/coroutine.py > > I hoped that "select-frame address ADDRESS" could be used instead so > this would work on coredumps too. Unfortunately "select-frame" only > searches stack frames that GDB is already aware of, so it cannot be used > to backtrace coroutine stacks. > > Is there a way to backtrace a stack at an arbitrary address in GDB?
I'm a bit surprised by this. Conceptually, why would GDB need to know about stack boundaries? Is there some heuristic to detect broken frames? Thanks, Florian
