From mboxrd@z Thu Jan  1 00:00:00 1970
From: Paul Mackerras <paulus@ozlabs.org>
Subject: Re: [PATCH v3 2/4] KVM: use simple waitqueue for vcpu->wq
Date: Wed, 21 Oct 2015 20:24:11 +1100
Message-ID: <20151021092411.GD15591@fergus.ozlabs.ibm.com>
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Cc: Daniel Wagner <daniel.wagner@bmw-carit.de>,
	linux-kernel@vger.kernel.org, linux-rt-users@vger.kernel.org,
	Marcelo Tosatti <mtosatti@redhat.com>,
	Paolo Bonzini <pbonzini@redhat.com>,
	"Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
	Paul Gortmaker <paul.gortmaker@windriver.com>,
	Thomas Gleixner <tglx@linutronix.de>
To: Peter Zijlstra <peterz@infradead.org>
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On Tue, Oct 20, 2015 at 04:00:31PM +0200, Peter Zijlstra wrote:
> 
> Should we not take this opportunity to get rid of these open-coded wait
> loops?
> 
> 
> Does this work?

No, on Book3S HV (POWER8) the VM hangs immediately after the kernel
brings up all the secondary vCPUs, and is then unkillable.  I'm not
sure what's wrong, although I wonder why you have TASK_IDLE rather
than TASK_INTERRUPTIBLE in the ___wait_event call.

Paul.