[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <BN9PR11MB52763F73D66CBBF6BEBA9B968CD7A@BN9PR11MB5276.namprd11.prod.outlook.com>
Date: Mon, 16 Oct 2023 08:26:25 +0000
From: "Tian, Kevin" <kevin.tian@...el.com>
To: Jason Gunthorpe <jgg@...dia.com>
CC: "Liu, Yi L" <yi.l.liu@...el.com>,
"joro@...tes.org" <joro@...tes.org>,
"alex.williamson@...hat.com" <alex.williamson@...hat.com>,
"robin.murphy@....com" <robin.murphy@....com>,
"baolu.lu@...ux.intel.com" <baolu.lu@...ux.intel.com>,
"cohuck@...hat.com" <cohuck@...hat.com>,
"eric.auger@...hat.com" <eric.auger@...hat.com>,
"nicolinc@...dia.com" <nicolinc@...dia.com>,
"kvm@...r.kernel.org" <kvm@...r.kernel.org>,
"mjrosato@...ux.ibm.com" <mjrosato@...ux.ibm.com>,
"chao.p.peng@...ux.intel.com" <chao.p.peng@...ux.intel.com>,
"yi.y.sun@...ux.intel.com" <yi.y.sun@...ux.intel.com>,
"peterx@...hat.com" <peterx@...hat.com>,
"jasowang@...hat.com" <jasowang@...hat.com>,
"shameerali.kolothum.thodi@...wei.com"
<shameerali.kolothum.thodi@...wei.com>,
"lulu@...hat.com" <lulu@...hat.com>,
"suravee.suthikulpanit@....com" <suravee.suthikulpanit@....com>,
"iommu@...ts.linux.dev" <iommu@...ts.linux.dev>,
"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
"linux-kselftest@...r.kernel.org" <linux-kselftest@...r.kernel.org>,
"Duan, Zhenzhong" <zhenzhong.duan@...el.com>,
"Martins, Joao" <joao.m.martins@...cle.com>
Subject: RE: [PATCH v4 05/17] iommufd: Separate kernel-managed HWPT
alloc/destroy/abort functions
> From: Jason Gunthorpe <jgg@...dia.com>
> Sent: Friday, October 13, 2023 10:06 PM
>
> On Fri, Oct 13, 2023 at 07:13:34AM +0000, Tian, Kevin wrote:
> > > From: Jason Gunthorpe <jgg@...dia.com>
> > > Sent: Friday, October 13, 2023 3:10 AM
> > >
> > > Also, we probably should feed enforce_cache_coherency through the
> > > alloc_hwpt uapi and not try to autodetect it..
> > >
> >
> > In the past we had a long discussion about this with the conclusion
> > that user opt is the ideal model but it's fine to stay with autodetect
> > and existing vfio/kvm contract for coherency detection until we
> > see a real demand for user opt.
> >
> > Is there anything new which changes your mind to have user opt now?
>
> I guess, I was just looking at the complexity it brings to keep that
> working.
>
vfio_file_enforced_coherent() currently just looks at device_iommu_capable()
and can be called before attach, assuming an autodetect model.
moving away from autodetect would need a new contract which I hesitate
to bother with at this point.
Powered by blists - more mailing lists