Comment 45 for bug 460857

I'm seeing behavior like this too. I'm running the 32-bit version of 10.10 on an Acer Aspire X3400, with kernel version:
2.6.35-23-generic #41-Ubuntu SMP

and an nVidia USB controller:
lspci | grep USB
00:02.0 USB Controller: nVidia Corporation MCP78S [GeForce 8200] OHCI USB 1.1 Controller (rev a1)
00:02.1 USB Controller: nVidia Corporation MCP78S [GeForce 8200] EHCI USB 2.0 Controller (rev a1)
00:04.0 USB Controller: nVidia Corporation MCP78S [GeForce 8200] OHCI USB 1.1 Controller (rev a1)
00:04.1 USB Controller: nVidia Corporation MCP78S [GeForce 8200] EHCI USB 2.0 Controller (rev a1)

The kernel log looks like this:

When the device is inserted:
[ 263.624073] usb 3-4: new full speed USB device using ohci_hcd and address 5
[ 263.858104] ftdi_sio 3-4:1.0: FTDI USB Serial Device converter detected
[ 263.858164] usb 3-4: Detected FT232RL
[ 263.858170] usb 3-4: Number of endpoints 2
[ 263.858176] usb 3-4: Endpoint 1 MaxPacketSize 64
[ 263.858181] usb 3-4: Endpoint 2 MaxPacketSize 64
[ 263.858186] usb 3-4: Setting MaxPacketSize 64
[ 263.861051] usb 3-4: FTDI USB Serial Device converter now attached to ttyUSB0

The FTDI chip works for a while, then stops transmitting data. When I try to close our java-based program that is using USB (ReplicatorG), I get this:
[ 720.488759] INFO: task java:2099 blocked for more than 120 seconds.
[ 720.488768] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[ 720.488775] java D f388fe1c 0 2099 1989 0x00000000
[ 720.488788] f388fe2c 00200086 00000002 f388fe1c 00000000 c05d89e0 c08c3700 c08c3700
[ 720.488804] 45cf69b9 0000007f c08c3700 c08c3700 45ced064 0000007f 00000000 c08c3700
[ 720.488818] c08c3700 f4434c20 00000001 f6453780 f6453788 f388fe34 f388fe54 c0471f7d
[ 720.488832] Call Trace:
[ 720.488849] [<c0471f7d>] usb_kill_urb+0x6d/0xa0
[ 720.488861] [<c0165eb0>] ? autoremove_wake_function+0x0/0x50
[ 720.488871] [<c047314c>] usb_start_wait_urb+0xac/0xc0
[ 720.488880] [<c04736e4>] usb_control_msg+0xc4/0x130
[ 720.488890] [<c04f537f>] ? __netif_receive_skb+0x33f/0x530
[ 720.488903] [<f81768ca>] ftdi_tiocmget+0xda/0x1ac [ftdi_sio]
[ 720.488916] [<f82ab14b>] serial_tiocmget+0x3b/0x80 [usbserial]
[ 720.488925] [<c03d9466>] tty_ioctl+0x2a6/0x620
[ 720.488933] [<c035a749>] ? copy_to_user+0x39/0x130
[ 720.488941] [<c0226a22>] vfs_ioctl+0x32/0xb0
[ 720.488948] [<c03d91c0>] ? tty_ioctl+0x0/0x620
[ 720.488955] [<c02272b9>] do_vfs_ioctl+0x79/0x2d0
[ 720.488961] [<c0227577>] sys_ioctl+0x67/0x80
[ 720.488970] [<c05c99f4>] syscall_call+0x7/0xb
[ 840.488110] INFO: task java:2099 blocked for more than 120 seconds.
[ 840.488119] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.

Kendrik's proposed workaround in #43 seems to recover a little better, but eventually this happens again.