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Date: Mon, 8 Dec 2014 16:38:15 +0100
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Subject: Re: [Qemu-devel] [RFC V2 10/10] cpus: reclaim allocated vCPU objects
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To: Peter Maydell <peter.maydell@linaro.org>
Cc: "qemu-devel@nongnu.org" <qemu-devel@nongnu.org>, tangchen@cn.fujitsu.com, ChenFan <chen.fan.fnst@cn.fujitsu.com>, isimatu.yasuaki@jp.fujitsu.com, Bharata B Rao <bharata.rao@gmail.com>, Gu Zheng <guz.fnst@cn.fujitsu.com>, Anshul Makkar <anshul.makkar@profitbricks.com>, "afaerber@suse.de" <afaerber@suse.de>

On Mon, 8 Dec 2014 10:50:21 +0000
Peter Maydell <peter.maydell@linaro.org> wrote:

> On 8 December 2014 at 10:28, Gu Zheng <guz.fnst@cn.fujitsu.com> wrote:
> > Yes, it's a limitation now, but it is not the final implementation.
> > As to the QEMU side, the vcpu object in kernel is stateless, and a
> > reset operation will be done when we hot add a vcpu, so I think we
> > can kill the limitation, just choose a parked vcpu and reconfigure
> > it before we use it.
> 
> Why can't the kernel handle our just destroying the vcpu and
> later recreating it if necessary? That seems the more logical
> approach than trying to keep fds hanging around in userspace
> for reuse.

It's somewhat complex approach and it was suggested on KVM list to go
parking route. for more details see thread
 https://www.mail-archive.com/kvm@vger.kernel.org/msg102839.html

> 
> -- PMM
>