On 01/03/18 04:15 PM, Bjorn Helgaas wrote:
The question is what the relevant switch is. We call pci_enable_acs() on every PCI device, including Root Ports. It looks like this relies on get_upstream_bridge_port() to filter out some things. I don't think get_upstream_bridge_port() is doing the right thing, so we need to sort that out first, I guess.
Yes, well if a port has an upstream bridge port and that port has an upstream bridge port we are almost certainly looking at a port in a switch. If you have a better suggestion to only disable ACS bits on downstream switch ports I'd be happy to consider it.
This might be a good start, but whatever the implications are, they need to be distilled and made clear directly in the changelog and the Kconfig help text.
Well, I tried. I'll expand on it for v3. Logan
