Re: 4.19 dwarf unwinding broken

From: Jiri Olsa
Date: Thu Oct 03 2019 - 06:03:04 EST


On Thu, Oct 03, 2019 at 12:54:09AM -0700, Josh Hunt wrote:
> The following commit is breaking dwarf unwinding on 4.19 kernels:

how?

jirka

>
> commit e5adfc3e7e774ba86f7bb725c6eef5f32df8630e
> Author: Konstantin Khlebnikov <khlebnikov@xxxxxxxxxxxxxx>
> Date: Tue Aug 7 12:09:01 2018 +0300
>
> perf map: Synthesize maps only for thread group leader
>
> It looks like this was fixed later by:
>
> commit e8ba2906f6b9054102ad035ac9cafad9d4168589
> Author: John Keeping <john@xxxxxxxxxxxx>
> Date: Thu Aug 15 11:01:45 2019 +0100
>
> perf unwind: Fix libunwind when tid != pid
>
> but was not selected as a backport to 4.19. Are there plans to backport the
> fix? If not, could we have the breaking commit reverted in 4.19 LTS?
>
> Thanks
> Josh