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Message-ID: <c1ff43de7d64831d8f40e8e11177f005b9940050.camel@sipsolutions.net>
Subject: Re: UML time-travel warning from __run_timers
From:   Johannes Berg <johannes@sipsolutions.net>
To:     Vincent Whitchurch <vincent.whitchurch@axis.com>
Cc:     linux-um@lists.infradead.org, linux-kernel@vger.kernel.org
Date:   Wed, 30 Mar 2022 14:33:23 +0200
In-Reply-To: <20220330110156.GA9250@axis.com>
References: <20220330110156.GA9250@axis.com>
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On Wed, 2022-03-30 at 13:01 +0200, Vincent Whitchurch wrote:
> Hello Johannes,
> 
> As requested in the roadtest thread[0], here is some information about
> reproducing the warnings I'm seeing from the timekeeping code with time
> travel in UML, after about 10-20 wall time seconds of idling.
> 
> [0] https://lore.kernel.org/lkml/5b39d572e619c812109af7a1b8028bfb8353efda.camel@sipsolutions.net/
> 
> The warning is the WARN_ON_ONCE(!levels && !base->next_expiry_recalc) in
> __run_timers().  The log and the config generated with savedefconfig are
> below.  The full .config is attached.
> 
> The kernel version is v5.17, but the splats are seen on older kernels
> and on latest mainline also.
> 

So interestingly, I cannot reproduce it with my config (it's already
March 2023), but I can with yours ...

johannes