Re: [PATCH 3/5] vfio/iommu_type1: Prefer to reuse domains vs match enforced cache coherency

On Wed, Jun 15, 2022 at 07:35:00AM +, Tian, Kevin wrote: > External email: Use caution opening links or attachments > > > > From: Nicolin Chen > > Sent: Wednesday, June 15, 2022 4:45 AM > > > > Hi Kevin, > > > > On Wed, Jun 08, 2022 at 11:48:27PM +, Tian, Kevin wrote: > > > > > > The KVM

RE: [PATCH 3/5] vfio/iommu_type1: Prefer to reuse domains vs match enforced cache coherency

> From: Nicolin Chen > Sent: Wednesday, June 15, 2022 4:45 AM > > Hi Kevin, > > On Wed, Jun 08, 2022 at 11:48:27PM +, Tian, Kevin wrote: > > > > > The KVM mechanism for controlling wbinvd is only triggered during > > > > > kvm_vfio_group_add(), meaning it is a one-shot test done once the > >

Re: [PATCH 3/5] vfio/iommu_type1: Prefer to reuse domains vs match enforced cache coherency

Hi Kevin, On Wed, Jun 08, 2022 at 11:48:27PM +, Tian, Kevin wrote: > > > > The KVM mechanism for controlling wbinvd is only triggered during > > > > kvm_vfio_group_add(), meaning it is a one-shot test done once the > > devices > > > > are setup. > > > > > > It's not one-shot. kvm_vfio_update_c

RE: [PATCH 3/5] vfio/iommu_type1: Prefer to reuse domains vs match enforced cache coherency

> From: Jason Gunthorpe > Sent: Wednesday, June 8, 2022 7:17 PM > > On Wed, Jun 08, 2022 at 08:28:03AM +, Tian, Kevin wrote: > > > From: Nicolin Chen > > > Sent: Monday, June 6, 2022 2:19 PM > > > > > > From: Jason Gunthorpe > > > > > > The KVM mechanism for controlling wbinvd is only trigge

Re: [PATCH 3/5] vfio/iommu_type1: Prefer to reuse domains vs match enforced cache coherency

On Wed, Jun 08, 2022 at 08:28:03AM +, Tian, Kevin wrote: > > From: Nicolin Chen > > Sent: Monday, June 6, 2022 2:19 PM > > > > From: Jason Gunthorpe > > > > The KVM mechanism for controlling wbinvd is only triggered during > > kvm_vfio_group_add(), meaning it is a one-shot test done once the

RE: [PATCH 3/5] vfio/iommu_type1: Prefer to reuse domains vs match enforced cache coherency

> From: Nicolin Chen > Sent: Monday, June 6, 2022 2:19 PM > > From: Jason Gunthorpe > > The KVM mechanism for controlling wbinvd is only triggered during > kvm_vfio_group_add(), meaning it is a one-shot test done once the devices > are setup. It's not one-shot. kvm_vfio_update_coherency() is ca

[PATCH 3/5] vfio/iommu_type1: Prefer to reuse domains vs match enforced cache coherency

From: Jason Gunthorpe The KVM mechanism for controlling wbinvd is only triggered during kvm_vfio_group_add(), meaning it is a one-shot test done once the devices are setup. So, there is no value in trying to push a device that could do enforced cache coherency to a dedicated domain vs re-using a