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Date:   Fri, 16 Jun 2023 15:48:35 -0300
From:   Jason Gunthorpe <jgg@nvidia.com>
To:     Alexander Duyck <alexander.duyck@gmail.com>
Cc:     "Tian, Kevin" <kevin.tian@intel.com>,
        Robin Murphy <robin.murphy@arm.com>,
        Alex Williamson <alex.williamson@redhat.com>,
        Baolu Lu <baolu.lu@linux.intel.com>,
        LKML <linux-kernel@vger.kernel.org>,
        linux-pci <linux-pci@vger.kernel.org>,
        "iommu@lists.linux.dev" <iommu@lists.linux.dev>
Subject: Re: Question about reserved_regions w/ Intel IOMMU
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On Fri, Jun 16, 2023 at 08:27:21AM -0700, Alexander Duyck wrote:

> > > The problem is that the user may not open all the devices then
> > > currently there is no way for it to know the windows on those
> > > unopened devices.
> > >
> > > Curious why nobody complains about this gap before this thread...
> >
> > Probably because it only matters if you have a real PCIe switch in the
> > system, which is pretty rare.
> 
> So just FYI I am pretty sure we have a partitioned PCIe switch that
> has FW issues.

Yeah, that is pretty common :(

But I think you've touched on a gap in the API.

Jason