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Cc:     baolu.lu@linux.intel.com,
        Jean-Philippe Brucker <jean-philippe@linaro.org>,
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        Kirti Wankhede <kwankhede@nvidia.com>,
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        <alex.williamson@redhat.com>,
        "iommu@lists.linux-foundation.org" <iommu@lists.linux-foundation.org>,
        Robin Murphy <robin.murphy@arm.com>,
        David Gibson <david@gibson.dropbear.id.au>
Subject: Re: [RFC] /dev/ioasid uAPI proposal
To:     Jason Gunthorpe <jgg@nvidia.com>,
        Liu Yi L <yi.l.liu@linux.intel.com>
References: <MWHPR11MB1886422D4839B372C6AB245F8C239@MWHPR11MB1886.namprd11.prod.outlook.com>
 <20210528233649.GB3816344@nvidia.com> <20210531193157.5494e6c6@yiliu-dev>
 <20210531180911.GX1002214@nvidia.com>
From:   Lu Baolu <baolu.lu@linux.intel.com>
Message-ID: <6ca65628-1c0e-4ae3-6357-1493f993349e@linux.intel.com>
Date:   Tue, 1 Jun 2021 11:08:53 +0800
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On 6/1/21 2:09 AM, Jason Gunthorpe wrote:
>>> device bind should fail if the device somehow isn't compatible with
>>> the scheme the user is tring to use.
>> yeah, I guess you mean to fail the device attach when the IOASID is a
>> nesting IOASID but the device is behind an iommu without nesting support.
>> right?
> Right..
>   

Just want to confirm...

Does this mean that we only support hardware nesting and don't want to
have soft nesting (shadowed page table in kernel) in IOASID?

Best regards,
baolu