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From:   Jason Gunthorpe <jgg@mellanox.com>
To:     "Dey, Megha" <megha.dey@linux.intel.com>
Cc:     Dan Williams <dan.j.williams@intel.com>,
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Subject: Re: [PATCH RFC 00/15] Add VFIO mediated device support and IMS
 support for the idxd driver.
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On Fri, May 01, 2020 at 03:31:51PM -0700, Dey, Megha wrote:
> > > This has been my concern reviewing the implementation. IMS needs more
> > > than one in-tree user to validate degrees of freedom in the api. I had
> > > been missing a second "in-tree user" to validate the scope of the
> > > flexibility that was needed.
> > 
> > IMS is too narrowly specified.
> > 
> > All platforms that support MSI today can support IMS. It is simply a
> > way for the platform to give the driver an addr/data pair that triggers
> > an interrupt when a posted write is performed to that pair.
> > 
> 
> Well, yes and no. IMS requires interrupt remapping in addition to the
> dynamic nature of IRQ allocation.

You've mentioned remapping a few times, but I really can't understand
why it has anything to do with platform_msi or IMS..

Jason