Re: (proposal) RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-11-04 Thread Jason Gunthorpe
On Tue, Nov 03, 2020 at 08:14:29PM +0100, j...@8bytes.org wrote: > On Tue, Nov 03, 2020 at 01:48:51PM -0400, Jason Gunthorpe wrote: > > I think the same PCI driver with a small flag to support the PF or > > VF is not the same as two completely different drivers in different > > subsystems > >

Re: (proposal) RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-11-03 Thread j...@8bytes.org
On Tue, Nov 03, 2020 at 01:48:51PM -0400, Jason Gunthorpe wrote: > I think the same PCI driver with a small flag to support the PF or > VF is not the same as two completely different drivers in different > subsystems There are counter-examples: ixgbe vs. ixgbevf. Note that also a single driver

Re: (proposal) RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-11-03 Thread Jason Gunthorpe
On Tue, Nov 03, 2020 at 05:55:40PM +0100, j...@8bytes.org wrote: > On Tue, Nov 03, 2020 at 11:22:23AM -0400, Jason Gunthorpe wrote: > > This whole thread was brought up by IDXD which has a SVA driver and > > now wants to add a vfio-mdev driver too. SVA devices that want to be > > plugged into VMs

Re: (proposal) RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-11-03 Thread j...@8bytes.org
On Tue, Nov 03, 2020 at 11:22:23AM -0400, Jason Gunthorpe wrote: > This whole thread was brought up by IDXD which has a SVA driver and > now wants to add a vfio-mdev driver too. SVA devices that want to be > plugged into VMs are going to be common - this architecture that a SVA > driver cannot

Re: (proposal) RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-11-03 Thread Jason Gunthorpe
On Tue, Nov 03, 2020 at 03:35:32PM +0100, j...@8bytes.org wrote: > On Tue, Nov 03, 2020 at 10:06:42AM -0400, Jason Gunthorpe wrote: > > The point is that other places beyond VFIO need this > > Which and why? > > > Sure, but sometimes it is necessary, and in those cases the answer > > can't be

Re: (proposal) RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-11-03 Thread j...@8bytes.org
On Tue, Nov 03, 2020 at 10:06:42AM -0400, Jason Gunthorpe wrote: > The point is that other places beyond VFIO need this Which and why? > Sure, but sometimes it is necessary, and in those cases the answer > can't be "rewrite a SVA driver to use vfio" This is getting to abstract. Can you come up

Re: (proposal) RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-11-03 Thread Jason Gunthorpe
On Tue, Nov 03, 2020 at 03:03:18PM +0100, j...@8bytes.org wrote: > On Tue, Nov 03, 2020 at 09:23:35AM -0400, Jason Gunthorpe wrote: > > Userspace needs fine grained control over the composition of the page > > table behind the PASID, 1:1 with the mm_struct is only one use case. > > VFIO already

Re: (proposal) RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-11-03 Thread Jason Gunthorpe
On Tue, Nov 03, 2020 at 02:18:52PM +0100, j...@8bytes.org wrote: > On Tue, Nov 03, 2020 at 08:56:43AM -0400, Jason Gunthorpe wrote: > > On Tue, Nov 03, 2020 at 10:52:09AM +0100, j...@8bytes.org wrote: > > > So having said this, what is the benefit of exposing those SVA internals > > > to

Re: (proposal) RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-11-03 Thread j...@8bytes.org
On Tue, Nov 03, 2020 at 08:56:43AM -0400, Jason Gunthorpe wrote: > On Tue, Nov 03, 2020 at 10:52:09AM +0100, j...@8bytes.org wrote: > > So having said this, what is the benefit of exposing those SVA internals > > to user-space? > > Only the device use of the PASID is device specific, the actual

Re: (proposal) RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-11-03 Thread Jason Gunthorpe
On Tue, Nov 03, 2020 at 10:52:09AM +0100, j...@8bytes.org wrote: > So having said this, what is the benefit of exposing those SVA internals > to user-space? Only the device use of the PASID is device specific, the actual PASID and everything on the IOMMU side is generic. There is enough API

Re: (proposal) RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-11-03 Thread j...@8bytes.org
On Mon, Oct 12, 2020 at 08:38:54AM +, Tian, Kevin wrote: > > From: Jason Wang > > Jason suggest something like /dev/sva. There will be a lot of other > > subsystems that could benefit from this (e.g vDPA). Honestly, I fail to see the benefit of offloading these IOMMU specific setup tasks to

Re: (proposal) RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-10-21 Thread Jason Wang
On 2020/10/22 上午11:54, Liu, Yi L wrote: Hi Jason, From: Jason Wang Sent: Thursday, October 22, 2020 10:56 AM [...] If you(Intel) don't have plan to do vDPA, you should not prevent other vendors from implementing PASID capable hardware through non-VFIO subsystem/uAPI on top of your SIOV

RE: (proposal) RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-10-21 Thread Liu, Yi L
Hi Jason, > From: Jason Wang > Sent: Thursday, October 22, 2020 10:56 AM > [...] > If you(Intel) don't have plan to do vDPA, you should not prevent other vendors > from implementing PASID capable hardware through non-VFIO subsystem/uAPI > on top of your SIOV architecture. Isn't it? yes, that's

Re: (proposal) RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-10-21 Thread Jason Wang
On 2020/10/22 上午1:51, Raj, Ashok wrote: On Wed, Oct 21, 2020 at 08:48:29AM -0300, Jason Gunthorpe wrote: On Tue, Oct 20, 2020 at 01:27:13PM -0700, Raj, Ashok wrote: On Tue, Oct 20, 2020 at 05:14:03PM -0300, Jason Gunthorpe wrote: On Tue, Oct 20, 2020 at 01:08:44PM -0700, Raj, Ashok wrote:

Re: (proposal) RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-10-21 Thread Raj, Ashok
On Wed, Oct 21, 2020 at 08:32:18PM -0300, Jason Gunthorpe wrote: > On Wed, Oct 21, 2020 at 01:03:15PM -0700, Raj, Ashok wrote: > > > I'm not sure why you tie in IDXD and VDPA here. How IDXD uses native > > SVM is orthogonal to how we achieve mdev passthrough to guest and > > vSVM. > > Everyone

Re: (proposal) RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-10-21 Thread Jason Gunthorpe
On Wed, Oct 21, 2020 at 01:03:15PM -0700, Raj, Ashok wrote: > I'm not sure why you tie in IDXD and VDPA here. How IDXD uses native > SVM is orthogonal to how we achieve mdev passthrough to guest and > vSVM. Everyone assumes that vIOMMU and SIOV aka PASID is going to be needed on the VDPA side as

Re: (proposal) RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-10-21 Thread Raj, Ashok
On Wed, Oct 21, 2020 at 03:24:42PM -0300, Jason Gunthorpe wrote: > > > Contrary to your argument, vDPA went with a half blown device only > > iommu user without considering existing abstractions like containers > > VDPA IOMMU was done *for Intel*, as the kind of half-architected thing > you are

Re: (proposal) RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-10-21 Thread Raj, Ashok
On Wed, Oct 21, 2020 at 08:48:29AM -0300, Jason Gunthorpe wrote: > On Tue, Oct 20, 2020 at 01:27:13PM -0700, Raj, Ashok wrote: > > On Tue, Oct 20, 2020 at 05:14:03PM -0300, Jason Gunthorpe wrote: > > > On Tue, Oct 20, 2020 at 01:08:44PM -0700, Raj, Ashok wrote: > > > > On Tue, Oct 20, 2020 at

Re: (proposal) RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-10-21 Thread Jason Gunthorpe
On Wed, Oct 21, 2020 at 10:51:46AM -0700, Raj, Ashok wrote: > > If they didn't plan to use it, bit of a strawman argument, right? > > This doesn't need to continue like the debates :-) Pun intended :-) > > I don't think it makes any sense to have an abstract strawman argument > design

Re: (proposal) RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-10-21 Thread Jason Gunthorpe
On Tue, Oct 20, 2020 at 01:27:13PM -0700, Raj, Ashok wrote: > On Tue, Oct 20, 2020 at 05:14:03PM -0300, Jason Gunthorpe wrote: > > On Tue, Oct 20, 2020 at 01:08:44PM -0700, Raj, Ashok wrote: > > > On Tue, Oct 20, 2020 at 04:55:57PM -0300, Jason Gunthorpe wrote: > > > > On Tue, Oct 20, 2020 at

Re: (proposal) RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-10-20 Thread Jason Wang
On 2020/10/20 下午10:19, Liu, Yi L wrote: From: Jason Gunthorpe Sent: Tuesday, October 20, 2020 10:02 PM [...] Whoever provides the vIOMMU emulation and relays the page fault to the guest has to translate the RID - that's the point. But the device info (especially the sub-device info) is

Re: (proposal) RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-10-20 Thread Raj, Ashok
On Tue, Oct 20, 2020 at 05:14:03PM -0300, Jason Gunthorpe wrote: > On Tue, Oct 20, 2020 at 01:08:44PM -0700, Raj, Ashok wrote: > > On Tue, Oct 20, 2020 at 04:55:57PM -0300, Jason Gunthorpe wrote: > > > On Tue, Oct 20, 2020 at 12:51:46PM -0700, Raj, Ashok wrote: > > > > I think we agreed (or agree

Re: (proposal) RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-10-20 Thread Jason Gunthorpe
On Tue, Oct 20, 2020 at 01:08:44PM -0700, Raj, Ashok wrote: > On Tue, Oct 20, 2020 at 04:55:57PM -0300, Jason Gunthorpe wrote: > > On Tue, Oct 20, 2020 at 12:51:46PM -0700, Raj, Ashok wrote: > > > I think we agreed (or agree to disagree and commit) for device types that > > > we have for SIOV,

Re: (proposal) RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-10-20 Thread Raj, Ashok
On Tue, Oct 20, 2020 at 04:55:57PM -0300, Jason Gunthorpe wrote: > On Tue, Oct 20, 2020 at 12:51:46PM -0700, Raj, Ashok wrote: > > I think we agreed (or agree to disagree and commit) for device types that > > we have for SIOV, VFIO based approach works well without having to > > re-invent > >

Re: (proposal) RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-10-20 Thread Jason Gunthorpe
On Tue, Oct 20, 2020 at 12:51:46PM -0700, Raj, Ashok wrote: > I think we agreed (or agree to disagree and commit) for device types that > we have for SIOV, VFIO based approach works well without having to re-invent > another way to do the same things. Not looking for a shortcut by any means, >

Re: (proposal) RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-10-20 Thread Raj, Ashok
On Tue, Oct 20, 2020 at 02:03:36PM -0300, Jason Gunthorpe wrote: > On Tue, Oct 20, 2020 at 09:24:30AM -0700, Raj, Ashok wrote: > > Hi Jason, > > > > > > On Tue, Oct 20, 2020 at 11:02:17AM -0300, Jason Gunthorpe wrote: > > > On Tue, Oct 20, 2020 at 10:21:41AM +, Liu, Yi L wrote: > > > > > >

Re: (proposal) RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-10-20 Thread Jason Gunthorpe
On Tue, Oct 20, 2020 at 09:24:30AM -0700, Raj, Ashok wrote: > Hi Jason, > > > On Tue, Oct 20, 2020 at 11:02:17AM -0300, Jason Gunthorpe wrote: > > On Tue, Oct 20, 2020 at 10:21:41AM +, Liu, Yi L wrote: > > > > > > I'm sure there will be some > > > > weird overlaps because we can't delete

Re: (proposal) RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-10-20 Thread Raj, Ashok
Hi Jason, On Tue, Oct 20, 2020 at 11:02:17AM -0300, Jason Gunthorpe wrote: > On Tue, Oct 20, 2020 at 10:21:41AM +, Liu, Yi L wrote: > > > > I'm sure there will be some > > > weird overlaps because we can't delete any of the existing VFIO APIs, but > > > that > > > should not be a blocker. >

RE: (proposal) RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-10-20 Thread Liu, Yi L
> From: Jason Gunthorpe > Sent: Tuesday, October 20, 2020 10:02 PM [...] > > > Whoever provides the vIOMMU emulation and relays the page fault to the > guest > > > has to translate the RID - > > > > that's the point. But the device info (especially the sub-device info) is > > within the passthru

RE: (proposal) RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-10-20 Thread Liu, Yi L
> From: Jason Gunthorpe > Sent: Tuesday, October 20, 2020 10:05 PM > To: Liu, Yi L > > On Tue, Oct 20, 2020 at 02:00:31PM +, Liu, Yi L wrote: > > > From: Jason Gunthorpe > > > Sent: Tuesday, October 20, 2020 9:55 PM > > > > > > On Tue, Oct 20, 2020 at 09:40:14AM +, Liu, Yi L wrote: > >

Re: (proposal) RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-10-20 Thread Jason Gunthorpe
On Tue, Oct 20, 2020 at 02:00:31PM +, Liu, Yi L wrote: > > From: Jason Gunthorpe > > Sent: Tuesday, October 20, 2020 9:55 PM > > > > On Tue, Oct 20, 2020 at 09:40:14AM +, Liu, Yi L wrote: > > > > > > See previous discussion with Kevin. If I understand correctly, you > > > > expect a >

Re: (proposal) RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-10-20 Thread Jason Gunthorpe
On Tue, Oct 20, 2020 at 10:21:41AM +, Liu, Yi L wrote: > > I'm sure there will be some > > weird overlaps because we can't delete any of the existing VFIO APIs, but > > that > > should not be a blocker. > > but the weird thing is what we should consider. And it perhaps not just > overlap, it

RE: (proposal) RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-10-20 Thread Liu, Yi L
> From: Jason Gunthorpe > Sent: Tuesday, October 20, 2020 9:55 PM > > On Tue, Oct 20, 2020 at 09:40:14AM +, Liu, Yi L wrote: > > > > See previous discussion with Kevin. If I understand correctly, you expect > > > a > shared > > > L2 table if vDPA and VFIO device are using the same PASID. >

Re: (proposal) RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-10-20 Thread Jason Gunthorpe
On Tue, Oct 20, 2020 at 09:40:14AM +, Liu, Yi L wrote: > > See previous discussion with Kevin. If I understand correctly, you expect a > > shared > > L2 table if vDPA and VFIO device are using the same PASID. > > L2 table sharing is not mandatory. The mapping is the same, but no need to >

RE: (proposal) RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-10-20 Thread Liu, Yi L
> From: Jason Gunthorpe > Sent: Monday, October 19, 2020 10:25 PM > > On Mon, Oct 19, 2020 at 08:39:03AM +, Liu, Yi L wrote: > > Hi Jason, > > > > Good to see your response. > > Ah, I was away got it. :-) > > > > > Second, IOMMU nested translation is a per IOMMU domain > > > > >

RE: (proposal) RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-10-20 Thread Liu, Yi L
> From: Jason Wang > Sent: Tuesday, October 20, 2020 5:20 PM > > Hi Yi: > > On 2020/10/20 ??4:19, Liu, Yi L wrote: > >> Yes, but since PASID is a global identifier now, I think kernel > >> should track the a device list per PASID? > > We have such track. It's done in iommu driver. You can refer

Re: (proposal) RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-10-20 Thread Jason Wang
Hi Yi: On 2020/10/20 下午4:19, Liu, Yi L wrote: Yes, but since PASID is a global identifier now, I think kernel should track the a device list per PASID? We have such track. It's done in iommu driver. You can refer to the struct intel_svm. PASID is a global identifier, but it doesn’t affect that

RE: (proposal) RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-10-20 Thread Liu, Yi L
Hey Jason, > From: Jason Wang > Sent: Tuesday, October 20, 2020 2:18 PM > > On 2020/10/15 ??6:14, Liu, Yi L wrote: > >> From: Jason Wang > >> Sent: Thursday, October 15, 2020 4:41 PM > >> > >> > >> On 2020/10/15 ??3:58, Tian, Kevin wrote: > From: Jason Wang > Sent: Thursday, October

Re: (proposal) RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-10-20 Thread Jason Wang
On 2020/10/15 下午6:14, Liu, Yi L wrote: From: Jason Wang Sent: Thursday, October 15, 2020 4:41 PM On 2020/10/15 ??3:58, Tian, Kevin wrote: From: Jason Wang Sent: Thursday, October 15, 2020 2:52 PM On 2020/10/14 ??11:08, Tian, Kevin wrote: From: Jason Wang Sent: Tuesday, October 13, 2020

Re: (proposal) RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-10-19 Thread Jason Gunthorpe
On Mon, Oct 19, 2020 at 08:39:03AM +, Liu, Yi L wrote: > Hi Jason, > > Good to see your response. Ah, I was away > > > > Second, IOMMU nested translation is a per IOMMU domain > > > > capability. Since IOMMU domains are managed by VFIO/VDPA > > > > (alloc/free domain, attach/detach device,

RE: (proposal) RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-10-19 Thread Liu, Yi L
Hi Jason, Good to see your response. > From: Jason Gunthorpe > Sent: Friday, October 16, 2020 11:37 PM > > On Wed, Oct 14, 2020 at 03:16:22AM +, Tian, Kevin wrote: > > Hi, Alex and Jason (G), > > > > How about your opinion for this new proposal? For now looks both > > Jason (W) and Jean

Re: (proposal) RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-10-16 Thread Jason Gunthorpe
On Wed, Oct 14, 2020 at 03:16:22AM +, Tian, Kevin wrote: > Hi, Alex and Jason (G), > > How about your opinion for this new proposal? For now looks both > Jason (W) and Jean are OK with this direction and more discussions > are possibly required for the new /dev/ioasid interface. Internally >

RE: (proposal) RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-10-15 Thread Liu, Yi L
> From: Jason Wang > Sent: Thursday, October 15, 2020 4:41 PM > > > On 2020/10/15 ??3:58, Tian, Kevin wrote: > >> From: Jason Wang > >> Sent: Thursday, October 15, 2020 2:52 PM > >> > >> > >> On 2020/10/14 ??11:08, Tian, Kevin wrote: > From: Jason Wang > Sent: Tuesday, October 13,

Re: (proposal) RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-10-15 Thread Jason Wang
On 2020/10/15 下午3:58, Tian, Kevin wrote: From: Jason Wang Sent: Thursday, October 15, 2020 2:52 PM On 2020/10/14 上午11:08, Tian, Kevin wrote: From: Jason Wang Sent: Tuesday, October 13, 2020 2:22 PM On 2020/10/12 下午4:38, Tian, Kevin wrote: From: Jason Wang Sent: Monday, September 14,

RE: (proposal) RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-10-15 Thread Tian, Kevin
> From: Jason Wang > Sent: Thursday, October 15, 2020 2:52 PM > > > On 2020/10/14 上午11:08, Tian, Kevin wrote: > >> From: Jason Wang > >> Sent: Tuesday, October 13, 2020 2:22 PM > >> > >> > >> On 2020/10/12 下午4:38, Tian, Kevin wrote: > From: Jason Wang > Sent: Monday, September 14,

Re: (proposal) RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-10-15 Thread Jason Wang
On 2020/10/15 上午7:10, Alex Williamson wrote: On Wed, 14 Oct 2020 03:08:31 + "Tian, Kevin" wrote: From: Jason Wang Sent: Tuesday, October 13, 2020 2:22 PM On 2020/10/12 下午4:38, Tian, Kevin wrote: From: Jason Wang Sent: Monday, September 14, 2020 12:20 PM [...] > If it's

Re: (proposal) RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-10-15 Thread Jason Wang
On 2020/10/14 上午11:08, Tian, Kevin wrote: From: Jason Wang Sent: Tuesday, October 13, 2020 2:22 PM On 2020/10/12 下午4:38, Tian, Kevin wrote: From: Jason Wang Sent: Monday, September 14, 2020 12:20 PM [...] > If it's possible, I would suggest a generic uAPI instead of a VFIO specific

Re: (proposal) RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-10-14 Thread Alex Williamson
On Wed, 14 Oct 2020 03:08:31 + "Tian, Kevin" wrote: > > From: Jason Wang > > Sent: Tuesday, October 13, 2020 2:22 PM > > > > > > On 2020/10/12 下午4:38, Tian, Kevin wrote: > > >> From: Jason Wang > > >> Sent: Monday, September 14, 2020 12:20 PM > > >> > > > [...] > > > > If it's

RE: (proposal) RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-10-13 Thread Tian, Kevin
Hi, Alex and Jason (G), How about your opinion for this new proposal? For now looks both Jason (W) and Jean are OK with this direction and more discussions are possibly required for the new /dev/ioasid interface. Internally we're doing a quick prototype to see any unforeseen issue with this

RE: (proposal) RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-10-13 Thread Tian, Kevin
> From: Jason Wang > Sent: Tuesday, October 13, 2020 2:22 PM > > > On 2020/10/12 下午4:38, Tian, Kevin wrote: > >> From: Jason Wang > >> Sent: Monday, September 14, 2020 12:20 PM > >> > > [...] > > > If it's possible, I would suggest a generic uAPI instead of a VFIO > >> specific one. > >> >

RE: (proposal) RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-10-13 Thread Tian, Kevin
> From: Jean-Philippe Brucker > Sent: Tuesday, October 13, 2020 6:28 PM > > On Mon, Oct 12, 2020 at 08:38:54AM +, Tian, Kevin wrote: > > > From: Jason Wang > > > Sent: Monday, September 14, 2020 12:20 PM > > > > > [...] > > > If it's possible, I would suggest a generic uAPI instead of a

Re: (proposal) RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-10-13 Thread Jean-Philippe Brucker
On Mon, Oct 12, 2020 at 08:38:54AM +, Tian, Kevin wrote: > > From: Jason Wang > > Sent: Monday, September 14, 2020 12:20 PM > > > [...] > > If it's possible, I would suggest a generic uAPI instead of a VFIO > > specific one. > > > > Jason suggest something like /dev/sva. There will be a lot

Re: (proposal) RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-10-13 Thread Jason Wang
On 2020/10/12 下午4:38, Tian, Kevin wrote: From: Jason Wang Sent: Monday, September 14, 2020 12:20 PM [...] > If it's possible, I would suggest a generic uAPI instead of a VFIO specific one. Jason suggest something like /dev/sva. There will be a lot of other subsystems that could benefit

(proposal) RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-10-12 Thread Tian, Kevin
> From: Jason Wang > Sent: Monday, September 14, 2020 12:20 PM > [...] > If it's possible, I would suggest a generic uAPI instead of a VFIO > specific one. > > Jason suggest something like /dev/sva. There will be a lot of other > subsystems that could benefit from this (e.g vDPA). > > Have you

Re: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-09-17 Thread Jason Wang
On 2020/9/18 上午2:17, Jacob Pan (Jun) wrote: Hi Jason, On Thu, 17 Sep 2020 11:53:49 +0800, Jason Wang wrote: On 2020/9/17 上午7:09, Jacob Pan (Jun) wrote: Hi Jason, On Wed, 16 Sep 2020 15:38:41 -0300, Jason Gunthorpe wrote: On Wed, Sep 16, 2020 at 11:21:10AM -0700, Jacob Pan (Jun) wrote:

Re: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-09-17 Thread Jacob Pan (Jun)
Hi Jason, On Thu, 17 Sep 2020 11:53:49 +0800, Jason Wang wrote: > On 2020/9/17 上午7:09, Jacob Pan (Jun) wrote: > > Hi Jason, > > On Wed, 16 Sep 2020 15:38:41 -0300, Jason Gunthorpe > > wrote: > > > >> On Wed, Sep 16, 2020 at 11:21:10AM -0700, Jacob Pan (Jun) wrote: > >>> Hi Jason, > >>> On

Re: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-09-17 Thread Jason Gunthorpe
On Thu, Sep 17, 2020 at 11:53:49AM +0800, Jason Wang wrote: > > > When VDPA is used by qemu it makes sense that the PASID will be an > > > arbitary IOVA map constructed to be 1:1 with the guest vCPU physical > > > map. /dev/sva allows a single uAPI to do this kind of setup, and qemu > > > can

RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-09-17 Thread Tian, Kevin
> From: Jason Gunthorpe > Sent: Wednesday, September 16, 2020 10:45 PM > > On Wed, Sep 16, 2020 at 01:19:18AM +, Tian, Kevin wrote: > > > From: Jason Gunthorpe > > > Sent: Tuesday, September 15, 2020 10:29 PM > > > > > > > Do they need a device at all? It's not clear to me why RID based >

Re: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-09-16 Thread Jason Wang
On 2020/9/17 上午7:09, Jacob Pan (Jun) wrote: Hi Jason, On Wed, 16 Sep 2020 15:38:41 -0300, Jason Gunthorpe wrote: On Wed, Sep 16, 2020 at 11:21:10AM -0700, Jacob Pan (Jun) wrote: Hi Jason, On Wed, 16 Sep 2020 14:01:13 -0300, Jason Gunthorpe wrote: On Wed, Sep 16, 2020 at 09:33:43AM

Re: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-09-16 Thread Jacob Pan (Jun)
Hi Jason, On Wed, 16 Sep 2020 15:38:41 -0300, Jason Gunthorpe wrote: > On Wed, Sep 16, 2020 at 11:21:10AM -0700, Jacob Pan (Jun) wrote: > > Hi Jason, > > On Wed, 16 Sep 2020 14:01:13 -0300, Jason Gunthorpe > > wrote: > > > > > On Wed, Sep 16, 2020 at 09:33:43AM -0700, Raj, Ashok wrote: > >

Re: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-09-16 Thread Jason Gunthorpe
On Wed, Sep 16, 2020 at 11:21:10AM -0700, Jacob Pan (Jun) wrote: > Hi Jason, > On Wed, 16 Sep 2020 14:01:13 -0300, Jason Gunthorpe > wrote: > > > On Wed, Sep 16, 2020 at 09:33:43AM -0700, Raj, Ashok wrote: > > > On Wed, Sep 16, 2020 at 12:07:54PM -0300, Jason Gunthorpe wrote: > > > > On Tue,

Re: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-09-16 Thread Jacob Pan (Jun)
Hi Jason, On Wed, 16 Sep 2020 14:01:13 -0300, Jason Gunthorpe wrote: > On Wed, Sep 16, 2020 at 09:33:43AM -0700, Raj, Ashok wrote: > > On Wed, Sep 16, 2020 at 12:07:54PM -0300, Jason Gunthorpe wrote: > > > On Tue, Sep 15, 2020 at 05:22:26PM -0700, Jacob Pan (Jun) wrote: > > > > > If user

Re: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-09-16 Thread Jason Gunthorpe
On Wed, Sep 16, 2020 at 09:33:43AM -0700, Raj, Ashok wrote: > On Wed, Sep 16, 2020 at 12:07:54PM -0300, Jason Gunthorpe wrote: > > On Tue, Sep 15, 2020 at 05:22:26PM -0700, Jacob Pan (Jun) wrote: > > > > If user space wants to bind page tables, create the PASID with > > > > /dev/sva, use ioctls

Re: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-09-16 Thread Auger Eric
Hi, On 9/16/20 6:32 PM, Jason Gunthorpe wrote: > On Wed, Sep 16, 2020 at 06:20:52PM +0200, Jean-Philippe Brucker wrote: >> On Wed, Sep 16, 2020 at 11:51:48AM -0300, Jason Gunthorpe wrote: >>> On Wed, Sep 16, 2020 at 10:32:17AM +0200, Jean-Philippe Brucker wrote: And this is the only PASID

Re: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-09-16 Thread Raj, Ashok
On Wed, Sep 16, 2020 at 12:07:54PM -0300, Jason Gunthorpe wrote: > On Tue, Sep 15, 2020 at 05:22:26PM -0700, Jacob Pan (Jun) wrote: > > > If user space wants to bind page tables, create the PASID with > > > /dev/sva, use ioctls there to setup the page table the way it wants, > > > then pass the

Re: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-09-16 Thread Jason Gunthorpe
On Wed, Sep 16, 2020 at 06:20:52PM +0200, Jean-Philippe Brucker wrote: > On Wed, Sep 16, 2020 at 11:51:48AM -0300, Jason Gunthorpe wrote: > > On Wed, Sep 16, 2020 at 10:32:17AM +0200, Jean-Philippe Brucker wrote: > > > And this is the only PASID model for Arm SMMU (and AMD IOMMU, I believe): > > >

Re: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-09-16 Thread Jean-Philippe Brucker
On Wed, Sep 16, 2020 at 11:51:48AM -0300, Jason Gunthorpe wrote: > On Wed, Sep 16, 2020 at 10:32:17AM +0200, Jean-Philippe Brucker wrote: > > And this is the only PASID model for Arm SMMU (and AMD IOMMU, I believe): > > the PASID space of a PCI function cannot be shared between host and guest, > >

Re: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-09-16 Thread Jason Gunthorpe
On Tue, Sep 15, 2020 at 05:22:26PM -0700, Jacob Pan (Jun) wrote: > > If user space wants to bind page tables, create the PASID with > > /dev/sva, use ioctls there to setup the page table the way it wants, > > then pass the now configured PASID to a driver that can use it. > > Are we talking

Re: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-09-16 Thread Jason Gunthorpe
On Wed, Sep 16, 2020 at 10:32:17AM +0200, Jean-Philippe Brucker wrote: > And this is the only PASID model for Arm SMMU (and AMD IOMMU, I believe): > the PASID space of a PCI function cannot be shared between host and guest, > so we assign the whole PASID table along with the RID. Since we need the

Re: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-09-16 Thread Jason Gunthorpe
On Wed, Sep 16, 2020 at 01:19:18AM +, Tian, Kevin wrote: > > From: Jason Gunthorpe > > Sent: Tuesday, September 15, 2020 10:29 PM > > > > > Do they need a device at all? It's not clear to me why RID based > > > IOMMU management fits within vfio's scope, but PASID based does not. > > > > In

Re: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-09-16 Thread Jean-Philippe Brucker
On Wed, Sep 16, 2020 at 01:19:18AM +, Tian, Kevin wrote: > > From: Jason Gunthorpe > > Sent: Tuesday, September 15, 2020 10:29 PM > > > > > Do they need a device at all? It's not clear to me why RID based > > > IOMMU management fits within vfio's scope, but PASID based does not. > > > > In

Re: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-09-15 Thread Jason Wang
On 2020/9/16 上午3:26, Raj, Ashok wrote: IIUC, you are asking that part of the interface to move to a API interface that potentially the new /dev/sva and VFIO could share? I think the API's for PASID management themselves are generic (Jean's patchset + Jacob's ioasid set management). Yes, the in

Re: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-09-15 Thread Jason Wang
On 2020/9/14 下午9:31, Jean-Philippe Brucker wrote: If it's possible, I would suggest a generic uAPI instead of a VFIO specific one. A large part of this work is already generic uAPI, in include/uapi/linux/iommu.h. This is not what I read from this series, all the following uAPI is VFIO

Re: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-09-15 Thread Lu Baolu
On 9/16/20 8:22 AM, Jacob Pan (Jun) wrote: If user space wants to bind page tables, create the PASID with /dev/sva, use ioctls there to setup the page table the way it wants, then pass the now configured PASID to a driver that can use it. Are we talking about bare metal SVA? If so, I don't see

RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-09-15 Thread Tian, Kevin
> From: Jason Gunthorpe > Sent: Tuesday, September 15, 2020 10:29 PM > > > Do they need a device at all? It's not clear to me why RID based > > IOMMU management fits within vfio's scope, but PASID based does not. > > In RID mode vfio-pci completely owns the PCI function, so it is more > natural

Re: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-09-15 Thread Jacob Pan (Jun)
Hi Jason, On Tue, 15 Sep 2020 20:51:26 -0300, Jason Gunthorpe wrote: > On Tue, Sep 15, 2020 at 03:08:51PM -0700, Jacob Pan wrote: > > > A PASID vIOMMU solution sharable with VDPA and VFIO, based on a > > > PASID control char dev (eg /dev/sva, or maybe /dev/iommu) seems > > > like a reasonable

Re: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-09-15 Thread Jason Gunthorpe
On Tue, Sep 15, 2020 at 03:08:51PM -0700, Jacob Pan wrote: > > A PASID vIOMMU solution sharable with VDPA and VFIO, based on a PASID > > control char dev (eg /dev/sva, or maybe /dev/iommu) seems like a > > reasonable starting point for discussion. > > I am not sure what can really be consolidated

Re: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-09-15 Thread Jason Gunthorpe
On Tue, Sep 15, 2020 at 12:26:32PM -0700, Raj, Ashok wrote: > > Yes, there is. There is a limited pool of HW PASID's. If one user fork > > bombs it can easially claim an unreasonable number from that pool as > > each process will claim a PASID. That can DOS the rest of the system. > > Not sure

Re: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-09-15 Thread Jacob Pan
Hi Jason, On Tue, 15 Sep 2020 15:45:10 -0300, Jason Gunthorpe wrote: > On Tue, Sep 15, 2020 at 11:11:54AM -0700, Raj, Ashok wrote: > > > PASID applies widely to many device and needs to be introduced with a > > > wide community agreement so all scenarios will be supportable. > > > > True,

Re: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-09-15 Thread Raj, Ashok
On Tue, Sep 15, 2020 at 03:45:10PM -0300, Jason Gunthorpe wrote: > On Tue, Sep 15, 2020 at 11:11:54AM -0700, Raj, Ashok wrote: > > > PASID applies widely to many device and needs to be introduced with a > > > wide community agreement so all scenarios will be supportable. > > > > True, reading

Re: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-09-15 Thread Jason Gunthorpe
On Tue, Sep 15, 2020 at 11:11:54AM -0700, Raj, Ashok wrote: > > PASID applies widely to many device and needs to be introduced with a > > wide community agreement so all scenarios will be supportable. > > True, reading some of the earlier replies I was clearly confused as I > thought you were

Re: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-09-15 Thread Raj, Ashok
On Tue, Sep 15, 2020 at 08:33:41AM -0300, Jason Gunthorpe wrote: > On Mon, Sep 14, 2020 at 03:44:38PM -0700, Raj, Ashok wrote: > > Hi Jason, > > > > I thought we discussed this at LPC, but still seems to be going in > > circles :-(. > > We discused mdev at LPC, not PASID. > > PASID applies

Re: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-09-15 Thread Jason Gunthorpe
On Mon, Sep 14, 2020 at 04:33:10PM -0600, Alex Williamson wrote: > Can you explain that further, or spit-ball what you think this /dev/sva > interface looks like and how a user might interact between vfio and > this new interface? When you open it you get some container, inside the container

Re: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-09-15 Thread Jason Gunthorpe
On Mon, Sep 14, 2020 at 03:44:38PM -0700, Raj, Ashok wrote: > Hi Jason, > > I thought we discussed this at LPC, but still seems to be going in > circles :-(. We discused mdev at LPC, not PASID. PASID applies widely to many device and needs to be introduced with a wide community agreement so all

Re: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-09-14 Thread Raj, Ashok
Hi Jason, I thought we discussed this at LPC, but still seems to be going in circles :-(. On Mon, Sep 14, 2020 at 04:00:57PM -0300, Jason Gunthorpe wrote: > On Mon, Sep 14, 2020 at 12:23:28PM -0600, Alex Williamson wrote: > > On Mon, 14 Sep 2020 14:41:21 -0300 > > Jason Gunthorpe wrote: > > >

Re: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-09-14 Thread Alex Williamson
On Mon, 14 Sep 2020 16:00:57 -0300 Jason Gunthorpe wrote: > On Mon, Sep 14, 2020 at 12:23:28PM -0600, Alex Williamson wrote: > > On Mon, 14 Sep 2020 14:41:21 -0300 > > Jason Gunthorpe wrote: > > > > > On Mon, Sep 14, 2020 at 10:58:57AM -0600, Alex Williamson wrote: > > > > > > > "its own

Re: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-09-14 Thread Jason Gunthorpe
On Mon, Sep 14, 2020 at 12:23:28PM -0600, Alex Williamson wrote: > On Mon, 14 Sep 2020 14:41:21 -0300 > Jason Gunthorpe wrote: > > > On Mon, Sep 14, 2020 at 10:58:57AM -0600, Alex Williamson wrote: > > > > > "its own special way" is arguable, VFIO is just making use of what's > > > being

Re: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-09-14 Thread Alex Williamson
On Mon, 14 Sep 2020 14:41:21 -0300 Jason Gunthorpe wrote: > On Mon, Sep 14, 2020 at 10:58:57AM -0600, Alex Williamson wrote: > > > "its own special way" is arguable, VFIO is just making use of what's > > being proposed as the uapi via its existing IOMMU interface. > > I mean, if we have a

Re: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-09-14 Thread Jason Gunthorpe
On Mon, Sep 14, 2020 at 10:58:57AM -0600, Alex Williamson wrote: > "its own special way" is arguable, VFIO is just making use of what's > being proposed as the uapi via its existing IOMMU interface. I mean, if we have a /dev/sva then it makes no sense to extend the VFIO interfaces with the same

Re: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-09-14 Thread Alex Williamson
On Mon, 14 Sep 2020 13:33:54 -0300 Jason Gunthorpe wrote: > On Mon, Sep 14, 2020 at 09:22:47AM -0700, Raj, Ashok wrote: > > Hi Jason, > > > > On Mon, Sep 14, 2020 at 10:47:38AM -0300, Jason Gunthorpe wrote: > > > On Mon, Sep 14, 2020 at 03:31:13PM +0200, Jean-Philippe Brucker wrote: > > >

Re: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-09-14 Thread Jason Gunthorpe
On Mon, Sep 14, 2020 at 09:22:47AM -0700, Raj, Ashok wrote: > Hi Jason, > > On Mon, Sep 14, 2020 at 10:47:38AM -0300, Jason Gunthorpe wrote: > > On Mon, Sep 14, 2020 at 03:31:13PM +0200, Jean-Philippe Brucker wrote: > > > > > > Jason suggest something like /dev/sva. There will be a lot of other

Re: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-09-14 Thread Raj, Ashok
Hi Jason, On Mon, Sep 14, 2020 at 10:47:38AM -0300, Jason Gunthorpe wrote: > On Mon, Sep 14, 2020 at 03:31:13PM +0200, Jean-Philippe Brucker wrote: > > > > Jason suggest something like /dev/sva. There will be a lot of other > > > subsystems that could benefit from this (e.g vDPA). > > > > Do

Re: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-09-14 Thread Jason Gunthorpe
On Mon, Sep 14, 2020 at 03:31:13PM +0200, Jean-Philippe Brucker wrote: > > Jason suggest something like /dev/sva. There will be a lot of other > > subsystems that could benefit from this (e.g vDPA). > > Do you have a more precise idea of the interface /dev/sva would provide, > how it would

Re: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-09-14 Thread Jean-Philippe Brucker
On Mon, Sep 14, 2020 at 12:20:10PM +0800, Jason Wang wrote: > > On 2020/9/10 下午6:45, Liu Yi L wrote: > > Shared Virtual Addressing (SVA), a.k.a, Shared Virtual Memory (SVM) on > > Intel platforms allows address space sharing between device DMA and > > applications. SVA can reduce programming

Re: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-09-14 Thread Jason Gunthorpe
On Mon, Sep 14, 2020 at 10:38:10AM +, Tian, Kevin wrote: > is widely used thus can better help verify the core logic with > many existing devices. For vSVA, vDPA support has not be started > while VFIO support is close to be accepted. It doesn't make much > sense by blocking the VFIO part

RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-09-14 Thread Tian, Kevin
> From: Jason Wang > Sent: Monday, September 14, 2020 4:57 PM > > On 2020/9/14 下午4:01, Tian, Kevin wrote: > >> From: Jason Wang > >> Sent: Monday, September 14, 2020 12:20 PM > >> > >> On 2020/9/10 下午6:45, Liu Yi L wrote: > >>> Shared Virtual Addressing (SVA), a.k.a, Shared Virtual Memory (SVM)

Re: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-09-14 Thread Jason Wang
On 2020/9/14 下午4:01, Tian, Kevin wrote: From: Jason Wang Sent: Monday, September 14, 2020 12:20 PM On 2020/9/10 下午6:45, Liu Yi L wrote: Shared Virtual Addressing (SVA), a.k.a, Shared Virtual Memory (SVM) on Intel platforms allows address space sharing between device DMA and applications. SVA

RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-09-14 Thread Tian, Kevin
> From: Jason Wang > Sent: Monday, September 14, 2020 12:20 PM > > On 2020/9/10 下午6:45, Liu Yi L wrote: > > Shared Virtual Addressing (SVA), a.k.a, Shared Virtual Memory (SVM) on > > Intel platforms allows address space sharing between device DMA and > > applications. SVA can reduce programming

Re: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs

2020-09-13 Thread Jason Wang
On 2020/9/10 下午6:45, Liu Yi L wrote: Shared Virtual Addressing (SVA), a.k.a, Shared Virtual Memory (SVM) on Intel platforms allows address space sharing between device DMA and applications. SVA can reduce programming complexity and enhance security. This VFIO series is intended to expose SVA