Re: [v3 0/5] plumb kvm/vfio to allow getting kvm from vfio_group

From: Xiao Guangrong <guangrong.xiao@linux.intel.com>
To: Jike Song <jike.song@intel.com>,
	pbonzini@redhat.com, alex.williamson@redhat.com
Cc: kwankhede@nvidia.com, cjia@nvidia.com, kevin.tian@intel.com,
	kvm@vger.kernel.org
Subject: Re: [v3 0/5] plumb kvm/vfio to allow getting kvm from vfio_group
Date: Mon, 31 Oct 2016 15:06:32 +0800	[thread overview]
Message-ID: <eb699ed9-41c8-e34a-18b7-d3a1ee6d1c62@linux.intel.com> (raw)
In-Reply-To: <1477895706-22824-1-git-send-email-jike.song@intel.com>

On 10/31/2016 02:35 PM, Jike Song wrote:
> So far KVM and VFIO are mostly transparent to each other.
> However, there are users who would rely on them both. For
> example, KVMGT relies on VFIO to mediate device operations,
> and it also relies on KVM for features such as guest page
> tracking. To do that, it needs to know which KVM instance
> a vfio_group is attached to.
>
> There is already a kvm_vfio device serving for similar purpose,
> this patchset extend it to allow external usrs like KVMGT to
> get KVM instance from the vfio_group.
>
>
> I picked one of Kirti's patchset from:
>
> 	https://lkml.org/lkml/2016/10/26/1119
>
> for the function to get the vfio_group from a given device.
>
>
> Changes v3:
> 	- don't touch kvm_put_kvm, vfio won't need it

Do not understand. vfio does not use it indeed, however, the
user of udata, i.e, KVMGT, should put kvm after vfio_group_get_kvm().