Re: [PATCH v7 0/7] KVM: x86: Allow Qemu/KVM to use PVH entry point

From: Paolo Bonzini
Date: Mon Nov 19 2018 - 13:25:51 EST


On 16/11/18 18:17, Maran Wilson wrote:
> On 11/16/2018 2:46 AM, Paolo Bonzini wrote:
>> On 17/04/18 01:09, Maran Wilson wrote:
>>> For certain applications it is desirable to rapidly boot a KVM virtual
>>> machine. In cases where legacy hardware and software support within the
>>> guest is not needed, Qemu should be able to boot directly into the
>>> uncompressed Linux kernel binary without the need to run firmware.
>>>
>>> There already exists an ABI to allow this for Xen PVH guests and the ABI
>>> is supported by Linux and FreeBSD:
>>>
>>> ÂÂÂ https://xenbits.xen.org/docs/unstable/misc/pvh.html
>>>
>>> This patch series would enable Qemu to use that same entry point for
>>> booting KVM guests.
>> Hi Maran, what happened to this series (and to the QEMU work)?
>
> Hi Paolo,
>
> Thank you for the reminder. Sorry, I have been wanting to continue this
> work for a while now, but our team has been pulled in other directions
> and this one ended up getting temporarily pushed down the priority stack.
>
> Let me discuss with my management and get back to you. I do want (and
> intend) to support and push this over the finish line.
>
> In the meantime, if there are any folks out there with a specific
> business need for getting this done sooner rather than later

Well, we are interested in using this to avoid the decompression cost of
booting a "container-like" VM image. I'm not sure what we will do about
that, but certainly getting this included in the upstream projects would
be a prerequisite.

If you really prefer to discuss things offlist, feel free to include me,
Stefan and Stefano.

Paolo

> and are
> able to invest a bit of time to collaborate on the remaining Qemu work,
> please feel free to ping me offline. We have some preliminary Qemu
> patches, but there is some additional work needed before they are ready
> wider review.
>
> Thanks,
> -Maran