new variation seen with last boot parameters:

Plugging in a usb flash disk, then rmmod and modprobe ohci_hcd didn't yield immediate "full speed" recognition but different errors with different hubs (same physical devices) trying at 
about the same time.


[46035.084073] usb 1-1: new full speed USB device using ohci_hcd and address 2
[46035.264064] usb 1-1: device descriptor read/64, error -62
[46035.548050] usb 1-1: device descriptor read/64, error -62
[46035.764073] usb 6-4: reset high speed USB device using ehci_hcd and address 7
[46050.876074] usb 6-4: device descriptor read/64, error -110
[46066.092088] usb 6-4: device descriptor read/64, error -110
[46066.372081] usb 1-1: new full speed USB device using ohci_hcd and address 3
[46066.552077] usb 1-1: device descriptor read/64, error -62
[46066.836077] usb 1-1: device descriptor read/64, error -62
[46067.052080] usb 6-4: reset high speed USB device using ehci_hcd and address 7
[46077.460074] usb 6-4: device not accepting address 7, error -110
[46077.636110] usb 1-1: new full speed USB device using ohci_hcd and address 4
[46078.044072] usb 1-1: device not accepting address 4, error -62
[46078.156086] usb 6-4: reset high speed USB device using ehci_hcd and address 7
[46088.564058] usb 6-4: device not accepting address 7, error -110
[46088.565547] scsi 5:0:0:0: Device offlined - not ready after error recovery
[46088.740055] usb 1-1: new full speed USB device using ohci_hcd and address 5
[46089.148062] usb 1-1: device not accepting address 5, error -62
[46089.149466] hub 1-0:1.0: unable to enumerate USB device on port 1
[46089.150807] usb 6-4: USB disconnect, address 7
[46089.264070] usb 6-4: new high speed USB device using ehci_hcd and address 8
[46104.376847] usb 6-4: device descriptor read/64, error -110
[46119.592071] usb 6-4: device descriptor read/64, error -110
[46119.808081] usb 6-4: new high speed USB device using ehci_hcd and address 9
[46134.920054] usb 6-4: device descriptor read/64, error -110
[46150.136071] usb 6-4: device descriptor read/64, error -110
[46150.352083] usb 6-4: new high speed USB device using ehci_hcd and address 10
[46160.760065] usb 6-4: device not accepting address 10, error -110
[46160.872076] usb 6-4: new high speed USB device using ehci_hcd and address 11
[46171.280469] usb 6-4: device not accepting address 11, error -110
[46171.283959] hub 6-0:1.0: unable to enumerate USB device on port 4
[46171.656085] usb 5-2: new full speed USB device using ohci_hcd and address 2
[46171.856968] usb 5-2: not running at top speed; connect to a high speed hub
[46171.926559] usb 5-2: configuration #1 chosen from 1 choice
[46171.954393] scsi6 : SCSI emulation for USB Mass Storage devices
[46171.968230] usb-storage: device found at 2
[46171.968251] usb-storage: waiting for device to settle before scanning
[46176.969430] usb-storage: device scan complete
[46176.976430] scsi 6:0:0:0: Direct-Access     Kingston DataTraveler 2.0 PMAP PQ: 0 ANSI: 0 CCS
[46177.637112] sd 6:0:0:0: [sdc] 3903488 512-byte hardware sectors (1999 MB)
[46177.644134] sd 6:0:0:0: [sdc] Write Protect is off
[46177.644144] sd 6:0:0:0: [sdc] Mode Sense: 23 00 00 00
[46177.644148] sd 6:0:0:0: [sdc] Assuming drive cache: write through
[46177.670103] sd 6:0:0:0: [sdc] 3903488 512-byte hardware sectors (1999 MB)
[46177.677112] sd 6:0:0:0: [sdc] Write Protect is off
[46177.677121] sd 6:0:0:0: [sdc] Mode Sense: 23 00 00 00
[46177.677124] sd 6:0:0:0: [sdc] Assuming drive cache: write through
[46177.680214]  sdc: sdc1
[46177.691746] sd 6:0:0:0: [sdc] Attached SCSI removable disk
[46177.692403] sd 6:0:0:0: Attached scsi generic sg3 type 0