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Date: Thu, 13 Jun 2024 20:36:05 -0300
From: Jason Gunthorpe <jgg@nvidia.com>
To: Bjorn Helgaas <helgaas@kernel.org>
Cc: Vidya Sagar <vidyas@nvidia.com>, "corbet@lwn.net" <corbet@lwn.net>,
	"bhelgaas@google.com" <bhelgaas@google.com>,
	Gal Shalom <galshalom@nvidia.com>,
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	Jon Hunter <jonathanh@nvidia.com>,
	Masoud Moshref Javadi <mmoshrefjava@nvidia.com>,
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	Robin Murphy <robin.murphy@arm.com>,
	"iommu@lists.linux.dev" <iommu@lists.linux.dev>,
	Alex Williamson <alex.williamson@redhat.com>
Subject: Re: [PATCH V3] PCI: Extend ACS configurability
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References: <20240612232301.GB19897@nvidia.com>
 <20240613220520.GA1085981@bhelgaas>
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On Thu, Jun 13, 2024 at 05:05:20PM -0500, Bjorn Helgaas wrote:

> It's unfortunate that this requires so much expert knowledge to use,
> but I guess we don't really have a good alternative.  The only way I
> can think of to help would be some kind of white paper or examples in
> Documentation/PCI/.

So far I am seeing the system supplier supply the appropriate
instructions.. It is already this way for set_pci, and yes, it is a
huge PITA.

At one point Steven Bates was talking about some ACPI tables to give
the OS more information but I don't think that went anywhere..

Jason