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Date: Tue, 28 Nov 2017 17:43:33 +0100 (CET)
From: Thomas Gleixner <tglx@linutronix.de>
To: Abhishek Shah <abhishek.shah@broadcom.com>
cc: Daniel Lezcano <daniel.lezcano@linaro.org>,
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        Vikram Prakash <vikram.prakash@broadcom.com>
Subject: Re: timer-sp804: sched_clock: issue after first suspend
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On Mon, 27 Nov 2017, Abhishek Shah wrote:
> Apart from this, I see following prints at times, can the above
> discussion be related to this behavior?
> [  320.448348] INFO: rcu_sched detected stalls on CPUs/tasks:
> [  320.454015]  3-...: (90 GPs behind) idle=162/140000000000001/0
> softirq=1220/1220 fqs=2462
> [  320.462540]  (detected by 1, t=5255 jiffies, g=518, c=517, q=37)
> [  320.468738] Task dump for CPU 3:
> [  320.472067] swapper/3       R  running task        0     0      1 0x00000022
> [  320.479341] Call trace:
> [  320.481869] [<ffff000008085828>] __switch_to+0x98/0xb0

I dont think so. That's an issue which plagues Paul McKenney for quite some
time. It's either caused by a timer not firing or a wakeup being lost. We
have no idea yet how to debug that.

Thanks,

	tglx