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Date: Fri, 20 Jun 2014 12:38:30 +0200
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Subject: Re: [Qemu-devel] [PATCH v5 10/12] hw/mips: malta: Add KVM support
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To: Aurelien Jarno <aurelien@aurel32.net>
Cc: Peter Maydell <peter.maydell@linaro.org>, James Hogan <james.hogan@imgtec.com>, kvm@vger.kernel.org, Gleb Natapov <gleb@redhat.com>, qemu-devel@nongnu.org, Sanjay Lal <sanjayl@kymasys.com>

Il 20/06/2014 11:10, Aurelien Jarno ha scritto:
> > My idea was to add a machines-specific option umkernel=on, and require it
> > in order to run KVM.  Later we can add umkernel=on support for TCG as well,
> > while umkernel=off with KVM requires virtualization extensions.
> >
> > The same option can disable pflash boot.
> >
> > What do you think?
>
> For what I understand the current KVM support in MIPS uses trap and
> emulate and thus doesn't need hardware support, just a recent kernel
> with the option enabled.

Yes, but work to support virtualization extensions is underway.  Patches 
were posted a few months ago.

> That's why I do wonder if there is a real point
> in supporting UM kernels in TCG mode.

Debugging, mainly.  It is sometimes useful to compare TCG with KVM on 
x86, and I suppose it could be the same on MIPS.

Paolo