On Wed, 15 Jan 2014, Dennis New wrote: > When listening to my usb-bluetooth audio headset, the usb subsystem (I > think) on my laptop crashes, the bluetooth/audio is lost, and my > mplayer program is left in an "uninterruptible sleep" (D) state and > cannot be killed. The only way to get my usb-audio working again is to > reboot. ... > The crash is difficult to reproduce, sometimes it can occur after a few > minutes of a clean boot, and sometimes after a few days. After the > audio/usb abruptly stops, the syslog simply says: > > kernel: ALSA sound/usb/endpoint.c:501 timeout: still 3 active urbs on > EP #3 > > And then after a few minutes (after enabling some kernel debugging > options), I get some call traces of the hung task(s), which have > "ohci_urb_dequeue" in common. > > http://dennisn.dyndns.org/guest/pubstuff/debug-usbaudio/crash1.log > http://dennisn.dyndns.org/guest/pubstuff/debug-usbaudio/crash2.log > http://dennisn.dyndns.org/guest/pubstuff/debug-usbaudio/crash3.log The logs show that the khubd thread is hung, waiting for the ohci-hcd driver to finish cancelling a transfer. > The problem is not with my device, since it occurs with another > identical piece of hardware. It maybe be a problem with my laptop, > since my friend does not seem to be experiencing this problem, although > her laptop does not use ohci-pci. > > My usb controllers are: > > 1002:4374 00:13.0 USB controller: Advanced Micro Devices [AMD] > nee ATI IXP SB400 USB Host Controller (prog-if 10 [OHCI]) > 1002:4375 00:13.1 USB controller: Advanced Micro Devices [AMD] > nee ATI IXP SB400 USB Host Controller (prog-if 10 [OHCI]) > 1002:4373 00:13.2 USB controller: Advanced Micro Devices [AMD] > nee ATI IXP SB400 USB2 Host Controller (prog-if 20 [EHCI]) Your first step in attacking this problem should be to use the most up-to-date kernel available, which at the moment is 3.13-rc8. Be sure to enable CONFIG_FRAME_POINTER along with CONFIG_USB_DEBUG. If the problem occurs again, collect a copy of the output from the dmesg command (_not_ a copy of the system log). Then go into /sys/kernel/debug/usb/ohci and collect copies of all the files in the two subdirectories. It may be necessary to apply some debugging patches to get more information. Alan Stern -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
