From mboxrd@z Thu Jan  1 00:00:00 1970
From: Paolo Bonzini <pbonzini@redhat.com>
Subject: Re: [PATCH v6 2/3] KVM: dynamic halt_poll_ns adjustment
Date: Thu, 3 Sep 2015 09:31:39 +0200
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Cc: Wanpeng Li <wanpeng.li@hotmail.com>,
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To: David Matlack <dmatlack@google.com>
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On 02/09/2015 21:23, David Matlack wrote:
> 
> I actually wasn't thinking about vcpu->halt_poll_ns though. If
> single_task_running() breaks us out of the loop we will "goto out" instead
> of scheduling. My suspicion is this will cause us to loop calling
> kvm_vcpu_block and starve the waiting task (at least until need_resched()),
> which would break the "only hog the cpu when idle" aspect of halt-polling.

That's definitely a bug, yes.

Paolo