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Date:   Mon, 31 Jul 2023 16:52:32 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Guenter Roeck <linux@roeck-us.net>
Cc:     Joel Fernandes <joel@joelfernandes.org>, paulmck@kernel.org,
        Pavel Machek <pavel@denx.de>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
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        linux-kernel@vger.kernel.org, torvalds@linux-foundation.org,
        akpm@linux-foundation.org, shuah@kernel.org, patches@kernelci.org,
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        srw@sladewatkins.net, rwarsow@gmx.de, conor@kernel.org,
        rcu@vger.kernel.org, Ingo Molnar <mingo@kernel.org>
Subject: Re: scheduler problems in -next (was: Re: [PATCH 6.4 000/227]
 6.4.7-rc1 review)
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On Mon, Jul 31, 2023 at 07:48:19AM -0700, Guenter Roeck wrote:

> > I've taken your config above, and the rootfs.ext2 and run-sh from x86/.
> > I've then modified run-sh to use:
> > 
> >    qemu-system-x86_64 -enable-kvm -cpu host
> > 
> > What I'm seeing is that some boots get stuck at:
> > 
> > [    0.608230] Running RCU-tasks wait API self tests
> > 
> > Is this the right 'problem' ?
> > 
> 
> 
> Yes, exactly.

Excellent! Let me prod that with something sharp, see what comes
creeping out.