Re: rcu_sched stall while waiting in csd_lock_wait()

From: Peter Zijlstra
Date: Wed Aug 02 2017 - 04:15:02 EST

On Wed, Aug 02, 2017 at 09:01:19AM +0530, Pratyush Anand wrote:
> Hi,
> I am observing following rcu_sched stall while executing `perf record -a --
> sleep 1` with one of the arm64 platform. It looks like that stalled cpu was
> waiting in csd_lock_wait() from where it never came out,and so the stall.
> Any help/pointer for further debugging would be very helpful. Problem also
> reproduced with 4.13.0-rc3.

I'm sitting on this patch:

please give that a spin.