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Date:   Tue, 29 Nov 2022 13:33:10 -0400
From:   Jason Gunthorpe <jgg@nvidia.com>
To:     Robin Murphy <robin.murphy@arm.com>
Cc:     Niklas Schnelle <schnelle@linux.ibm.com>,
        Baolu Lu <baolu.lu@linux.intel.com>,
        Matthew Rosato <mjrosato@linux.ibm.com>,
        Gerd Bayer <gbayer@linux.ibm.com>, iommu@lists.linux.dev,
        Joerg Roedel <joro@8bytes.org>, Will Deacon <will@kernel.org>,
        Wenjia Zhang <wenjia@linux.ibm.com>,
        Pierre Morel <pmorel@linux.ibm.com>,
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        svens@linux.ibm.com, linux-kernel@vger.kernel.org,
        Julian Ruess <julianr@linux.ibm.com>
Subject: Re: [PATCH v2 4/7] iommu: Let iommu.strict override
 ops->def_domain_type
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On Mon, Nov 28, 2022 at 09:01:43PM +0000, Robin Murphy wrote:

> I'm hardly an advocate for trying to save users from themselves, but I
> honestly can't see any justifiable reason for not having sysfs respect
> iommu_get_def_domain_type(). 

We really need to rename this value if it is not actually just an
advisory "default" but a functional requirement ..

> > The driver should have no say in how dma-iommu.c works beyond if it
> > provides the required ops functionalities, and hint(s) as to what
> > gives best performance.
> 
> That should already be the case today, as outlined in my other mail. It's
> just somewhat more evolved than designed, so may not be so clear to
> everyone.

It is close to being clear, once we get the last touches of dma-iommu
stuff out of the drivers it should be quite clear

Thanks,
Jason