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From: Philippe Gerum <rpm@xenomai.org>
To: Bryan Butler <Bryan.Butler@kratosdefense.com>
Cc: Russell Johnson <russell.johnson@kratosdefense.com>,
 "xenomai@lists.linux.dev" <xenomai@lists.linux.dev>
Subject: Re: [External] - Re: System hanging when using condition variables
Date: Sun, 25 Sep 2022 16:59:24 +0200
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Philippe Gerum <rpm@xenomai.org> writes:

> Bryan Butler <Bryan.Butler@kratosdefense.com> writes:
>
>> I have another system that behaves slightly differently. When it hits the watchdog, here's what I get:
>>
>
> I have been able to reproduce a bug on an armv7 SoC with the test case
> you provided. Sometimes the RCU stall detector triggers, sometimes it's
> a plain hard lockup. I believe these are symptoms of the same bug, which
> _seems_ to hide in the PI chain management. I'm on it.

Actually, the PI chain was 'only' collateral damage. The bug was a
fairly silly ABBA deadlock issue elsewhere, in the monitor
implementation. A fix is under stress test here, I'll follow up with a
patch asap.

Thanks for the fine test case, having it made a huge difference once
again.

-- 
Philippe.