Hi Alex On Fri, May 9, 2014 at 11:28 PM, Alex Williamson <alex.williamson@xxxxxxxxxx> wrote: > .... > > Original description: > > This series attempts to fix a couple issues we've had outstanding in > the PCI/IOMMU code for a while. The first issue is with devices that > use the wrong requester ID for DMA transactions. We already have a > sort of half-baked attempt to fix this for several Ricoh devices, but > the fix only helps them be useful through IOMMU groups, not the > general DMA case. There are also several Marvell devices which use > use a different wrong requester ID and don't even fit into the DMA > source idea. This series creates a DMA alias iterator that will > step through each possible alias of a device, allowing IOMMUs to > insert mappings for both the device and its aliases. > > Hand-in-hand with this is our broken pci_find_upstream_pcie_bridge() > function, which is known to blowup when it finds itself suddenly at > a PCIe device without crossing a PCIe-to-PCI bridge (as identified by > the PCIe capability). It also likes to make the invalid assumption > that a PCIe device never has its requester ID masked by any usptream > bus. We can fix this using the above new DMA alias iterator, since > that's effectively what this function was meant to do. > There are two cases where the DMA requester id seems to use the wrong slot (as opposed to function) in the patch I attached to https://bugzilla.kernel.org/show_bug.cgi?id=42679 The original bug reports are listed in the patch. Unfortunately, I wasn't able to get test feedback on those two cases, but I'm wondering... Did I understand correctly that a slot alias is something that could be needed? If so, is it a variation of the PCIe-to-PCI bridge case that's already covered or will it require a different approach? Thanks, a. -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
