> -----Original Message----- > From: Wood Scott-B07421 > Sent: Friday, December 02, 2011 11:57 PM > To: Bhushan Bharat-R65777 > Cc: Stuart Yoder; Alex Williamson; Alexey Kardashevskiy; > aafab...@cisco.com; k...@vger.kernel.org; p...@au1.ibm.com; qemu- > de...@nongnu.org; joerg.roe...@amd.com; konrad.w...@oracle.com; > ag...@suse.de; d...@au1.ibm.com; chr...@sous-sol.org; Yoder Stuart-B08248; > io...@lists.linux-foundation.org; a...@redhat.com; linux- > p...@vger.kernel.org; Wood Scott-B07421; be...@cisco.com > Subject: Re: [Qemu-devel] [RFC PATCH] vfio: VFIO Driver core framework > > On 12/02/2011 12:11 PM, Bhushan Bharat-R65777 wrote: > > How do we determine whether guest is ready or not? There can be > multiple device get ready at different time. > > The guest makes a hypercall with a device handle -- at least that's how > we do it in Topaz. > > > Further if guest have given the device to it user level process or its > guest. Should not there be some mechanism for a guest to enable/disable > on per device or group? > > Yes, the same mechanism can be used for that -- though in that case we'll > also want the ability for the guest to be able to control another layer > of mapping (which will get quite tricky with PAMU's limitations). > This isn't really VFIO's concern, though (unless you're talking about > the VFIO implementation in the guest).
Scott, I am not sure if there is any real use case where device needed to assigned beyond 2 level (host + immediate guest) in nested virtualization. But if there any exists then will not it be better to virtualizes the iommu (PAMU for Freescale)? Thanks -Bharat
