Re: [RFC PATCH v1.9 07/14] x86/stacktrace: add function for detecting reliable stack traces

From: Jiri Slaby
Date: Thu Jun 09 2016 - 04:31:32 EST


On 04/12/2016, 05:56 PM, Josh Poimboeuf wrote:
>> We had been using unwinder for over a decade in SUSE but it stopped
>> working for assembly recently (for obvious reasons). So having a working
>> and reliable unwinder again is one of the top priorities for us.
>
> Since you already have an unwinder in SUSE, it sounds like what you need
> most urgently is DWARF generation support in objtool so that your
> unwinder will work again for asm code, right? The kernel already emits
> DWARF today (for C code), so an upstream unwinder isn't needed first.

Right, that's exact.

> That's high on my TODO list, and the coding is probably 70-80% done. I
> don't want to hold up progress... But I don't really feel comfortable
> passing the code off because it's quite a big feature with some major
> changes to objtool. Being the objtool author, I want to make sure to
> give it my full attention.

Sure. There is going to be no pressure to merge the v1 of the changes.
But it would be nice to see what you have now so that we can start
reviewing and proposing patches on the top of what you have :).

> I'm spread quite thin at the moment but I do hope to have v1 of those
> patches soon, hopefully May-ish.

So I hope we will see something we can start working on now. I can
really dedicate one-man hours to that work.

thanks,
--
js
suse labs