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Date:   Mon, 31 May 2021 12:24:47 -0300
From:   Jason Gunthorpe <jgg@nvidia.com>
To:     Thomas Gleixner <tglx@linutronix.de>
Cc:     Dave Jiang <dave.jiang@intel.com>, alex.williamson@redhat.com,
        kwankhede@nvidia.com, vkoul@kernel.org, megha.dey@intel.com,
        jacob.jun.pan@intel.com, ashok.raj@intel.com, yi.l.liu@intel.com,
        baolu.lu@intel.com, kevin.tian@intel.com, sanjay.k.kumar@intel.com,
        tony.luck@intel.com, dan.j.williams@intel.com,
        eric.auger@redhat.com, pbonzini@redhat.com,
        dmaengine@vger.kernel.org, linux-kernel@vger.kernel.org,
        kvm@vger.kernel.org
Subject: Re: [PATCH v6 05/20] vfio: mdev: common lib code for setting up
 Interrupt Message Store
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On Mon, May 31, 2021 at 03:48:35PM +0200, Thomas Gleixner wrote:

> What's unclear to me is under which circumstances does the IMS interrupt
> require a PASID.
> 
>    1) Always
>    2) Use case dependent

It is just a weird IDXD thing. The PASID is serving as some VM
identifier in that HW, somehow, AFAIK.

Jason