On Tue, Jul 22, 2014 at 05:52:00PM -0600, Bjorn Helgaas wrote: > If there is a hardware defect, a PCI quirk is a reasonable way to work > around it, since that's the main purpose of quirks. fixup_mpss_256() > is an example of something that sounds superficially similar. It was my suggestion to engage the PCI-E tuning code. By my understanding the HW bug is that read response segmentation at the host bridge does not work - so all read requests from any downstream device must have responses that fit within a single packet. This is completely against how the spec envisions things working, segmentation is a mandatory function. As you point out there is no parameter bounding the maximum read request size that a completer will accept. So, the only fix is that every downstream device must always have a MRSS set to less than the MPS of the host bridge. Which means the tuning code must be involved somehow, as that code controls the MRSS of unrelated devices... Regards, Jason -- 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
