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Date:   Mon, 4 May 2020 09:14:01 -0300
From:   Jason Gunthorpe <jgg@ziepe.ca>
To:     "Dey, Megha" <megha.dey@linux.intel.com>
Cc:     Dave Jiang <dave.jiang@intel.com>, vkoul@kernel.org,
        maz@kernel.org, bhelgaas@google.com, rafael@kernel.org,
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Subject: Re: [PATCH RFC 04/15] drivers/base: Add support for a new IMS irq
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On Sun, May 03, 2020 at 05:25:28PM -0700, Dey, Megha wrote:
> > > The use case if when we have a device assigned to a guest and we
> > > want to allocate IMS(platform-msi) interrupts for that
> > > guest-assigned device. Currently, this is abstracted through a mdev
> > > interface.
> > 
> > And the mdev has the pci_device internally, so it should simply pass
> > that pci_device to the platform_msi machinery.
> 
> hmm i am not sure I follow this. mdev has a pci_device internally? which
> struct are you referring to here?

mdev in general may not, but any ADI trying to use mdev will
necessarily have access to a struct pci_device.

> mdev is merely a micropartitioned PCI device right, which no real PCI
> resource backing. I am not how else we can find the IRQ domain associated
> with an mdev..

ADI always has real PCI resource backing.

Jason