On Fri, 7 Feb 2014, Dan Williams wrote: > >> + /* power on our usb3 peer before this usb2 port to prevent a usb3 > >> + * device from degrading to its usb2 connection > >> + */ > >> + if (!hub_is_superspeed(hdev) && peer) > >> + pm_runtime_get_sync(&peer->dev); > >> + > > > > Have you considered what would happen if this runs before the ACPI data > > causes the peers to be re-matched? > > If userspace is sets pm_qos_no_poweroff to 0 before we have figured > out the peer then suspending this port may lead to a disconnect.
What if userspace sets pm_qos_no_poweroff to 0 _after_ we have figured out the peer and _before_ the ACPI data causes us to change the peer? Alan Stern -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
