usb error -71

[   54.210000] usb 1-1: new high speed USB device using fsl-ehci and address 2
[   51.330000] usb 1-1: device descriptor read/64, error -71
[   51.560000] usb 1-1: device descriptor read/64, error -71
[   54.790000] usb 1-1: new high speed USB device using fsl-ehci and address 3
[   51.910000] usb 1-1: device descriptor read/64, error -71
[   51.140000] usb 1-1: device descriptor read/64, error -71
[   54.370000] usb 1-1: new high speed USB device using fsl-ehci and address 4
[   51.790000] usb 1-1: device not accepting address 4, error -71
[   54.910000] usb 1-1: new high speed USB device using fsl-ehci and address 5
[   51.330000] usb 1-1: device not accepting address 5, error -71
[   54.960000] usb 1-1: new high speed USB device using fsl-ehci and address 6
[   51.080000] usb 1-1: device descriptor read/64, error -71
[   51.450000] usb 1-1: device descriptor read/64, error -71
[   54.890000] usb 1-1: new high speed USB device using fsl-ehci and address 7
[   51.250000] usb 1-1: device descriptor read/64, error -71
[   51.490000] usb 1-1: device descriptor read/64, error -71
[   54.770000] usb 1-1: new high speed USB device using fsl-ehci and address 8
[   51.320000] usb 1-1: device not accepting address 8, error -71

これだとrebootしても無理で、haltして電源を切ってからじゃないと復活しない。