[Lldb-commits] [PATCH] D12968: Fix for lldb-mi crash in Listener code if -exec-abort MI command was invoked without getting process stopped

[Pavel Labath via lldb-commits]

labath added a comment.

In http://reviews.llvm.org/D12968#251696, @KLapshin wrote:

> Regarding matter of this patch - I just tried to make process stop synchronous, see Process::ResumeSynchronous() - same technique was applied months ago (@ki.stfu).
>
> Agreed what crash may be related to freed memory reuse, but not investigated it yet in deep.


Fair enough, your patch definitely makes things better. I'm just trying to understand the root cause so we can fix this definitively.

If you look at ResumeSynchronous, you see that the hijacking happens there before we attempt to resume the process (PrivateResume()). This makes it race-free because we grab the events before it gets a chance to generate any. In your case, things are a bit more complicated, since the process is already running and can come to a stop at any moment, and we need to make sure we don't miss those events.

Do you have the ability to run lldb-mi under valgrind or msan? If you can, I'd be interested in taking a look at the output they produce in this case. Or if you have a simple repro case, I can try to do it myself.

pl


Repository:
  rL LLVM

http://reviews.llvm.org/D12968