Comment 39 for bug 1810239

Created attachment 109981
Patch with quirk for incorrect PCI requester IDs

Here's a patch that provides a quirk for what I believe to be the root cause: devices that use incorrect PCI requester IDs, including Marvell 91xx controllers.

Various revisions have been sent to LKML and IOMMU-list in the past and a number of people have reported that it solved their problem and I've been running this on two boxes for months. I'm not sure why it hasn't been accepted.

Note that there are several devices that suffer from the same affliction, i.e., using incorrect PCI requester IDs in when their transactions. The Marvell devices use both xx:yy.0 and xx:yy.1, possibly related to the SATA port number. Other devices, like Ricoh's R5C832 PCIe IEEE 1394 Controller commonly found in T410 and T420 Thinkpads use a single incorrect requester ID.

Please try this patch and let me know if it works for you.