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References: <20160526163549.3276-4-a.rigo@virtualopensystems.com>
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From: Sergey Fedorov <serge.fdrv@gmail.com>
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Date: Wed, 8 Jun 2016 17:53:54 +0300
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Subject: Re: [Qemu-devel] [RFC 03/10] cpus: Introduce async_wait_run_on_cpu()
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To: alvise rigo <a.rigo@virtualopensystems.com>, =?UTF-8?Q?Alex_Benn=c3=a9e?= <alex.bennee@linaro.org>
Cc: MTTCG Devel <mttcg@listserver.greensocs.com>, QEMU Developers <qemu-devel@nongnu.org>, Jani Kokkonen <jani.kokkonen@huawei.com>, Claudio Fontana <claudio.fontana@huawei.com>, VirtualOpenSystems Technical Team <tech@virtualopensystems.com>, =?UTF-8?B?S09OUkFEIEZyw6lkw6lyaWM=?= <fred.konrad@greensocs.com>, Paolo Bonzini <pbonzini@redhat.com>, Richard Henderson <rth@twiddle.net>, "Emilio G. Cota" <cota@braap.org>, Peter Maydell <peter.maydell@linaro.org>

On 08/06/16 17:10, alvise rigo wrote:
> Using run_on_cpu() we might deadlock QEMU if other vCPUs are waiting
> for the current vCPU. We need to exit from the vCPU loop in order to
> avoid this.

I see, we could deadlock indeed. Alternatively, we may want fix
run_on_cpu() to avoid waiting for completion by itself when called from
CPU loop.

Kind regards,
Sergey