Messages in this thread | | | Date | Wed, 24 Aug 2022 11:23:21 -0500 | From | Bjorn Helgaas <> | Subject | Re: [PATCH v11 04/13] PCI: Allow PASID only when ACS enforced on upstreaming path |
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On Tue, Aug 23, 2022 at 03:05:53PM +0800, Baolu Lu wrote: > On 2022/8/19 07:00, Bjorn Helgaas wrote:
> > PCI: Enable PASID only when ACS RR & UF enabled on upstream path > > > > The Requester ID/Process Address Space ID (PASID) combination > > identifies an address space distinct from the PCI bus address space, > > e.g., an address space defined by an IOMMU. > > > > But the PCIe fabric routes Memory Requests based on the TLP address, > > ignoring any PASID (PCIe r6.0, sec 2.2.10.4), so a TLP with PASID that > > *should* go upstream to the IOMMU may instead be routed as a P2P > > Request if its address falls in a bridge window. > > > > To ensure that all Memory Requests with PASID are routed upstream, > > only enable PASID if ACS P2P Request Redirect and Upstream Forwarding > > are enabled for the path leading to the device. > > Yours is clear and straight-forward. I will update the patch with above. > Thank you and very appreciated!
With the update to only require RR and UF and the commit log update,
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Thanks!
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