Comment 680 for bug 88746

Most of these weird problems seem to occur if (and only if) I use a PCI USB controller plugged into a PCI-X slot of my IBM xSeries server.

Some facts:
* Tried two USB controllers, NEC and VIA.
* NEC works fine when only one mass storage device is plugged in. Resets occur otherwise.
* NEC doesn't like webcams. The image is either choppy or just black, varies from (kernel) version to version.
* VIA doesn't support mass storage at all. Numerous I/O errors pop up immediately when a device is connected.
* VIA supports webcams, but only at UHCI speeds. When a EHCI-only webcam is plugged in, it is detected, but doesn't work.

But here comes the most important fact of all: There are *no* such problems on other Linux machines I run. For example, USB now works fine on my laptop. I can connect my DVB-T receiver, pen drive, bluetooth dongle, webcam and other crazy devices at once and nothing bad happens.

Perhaps there's something wrong with PCI USB controllers in PCI-X slots. Unfortunately, the server is in use, so I can't bring it down and test USB thoroughly.