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Date:   Fri, 13 Oct 2023 11:05:38 -0300
From:   Jason Gunthorpe <jgg@nvidia.com>
To:     "Tian, Kevin" <kevin.tian@intel.com>
Cc:     "Liu, Yi L" <yi.l.liu@intel.com>,
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Subject: Re: [PATCH v4 05/17] iommufd: Separate kernel-managed HWPT
 alloc/destroy/abort functions
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On Fri, Oct 13, 2023 at 07:13:34AM +0000, Tian, Kevin wrote:
> > From: Jason Gunthorpe <jgg@nvidia.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.

Jason