Bug#774115: Bug resolution

[guillaume.jaouen@free.fr]

Hello dear maintainers,

After doing more research on the bug I reported for linux kernel driver xhci_hcd on Debian stable release, I realized that repeated connections and disconnections were all related to my external USB 3.0 dock.

Although it is powered by an AC adapter delivering three amps, I found that if I was using only one hard drive bay the phenomenon disappeared.

Once again I use the two drive bays, errors do reappearance in the kernel logs.

I think this is due to the fact that large hard disks (> 2TB) consume more power than conventional hard drives. This is imperceptible on external USB 3.0 devices but enough to cause stalls of the link.

I waited several days before posting this message to ensure that the situation was well restored.

I think that a warning to the attention of USB 3.0 ports users on this point should be included in the documentation, perhaps in the Debian wiki if a page is dedicated to suport the USB 3.0 bus.

sincerely,
Guillaume JAOUEN