Hi Daniel, thank you for your quick answer! On 7. 8. 2011 Daniel Mack wrote: > On Sun, Aug 7, 2011 at 11:04 PM, Matěj Laitl <matej@xxxxxxxx> wrote: > > every time I try to play a sound file though a NI Audio 4 DJ USB > > soundcard (snd-usb-caiaq module) that is connected to a NEC Corporation > > uPD720200 USB 3.0 Host Controller (xhci-hcd module), the system > > completely hangs. dmesg reports stalls or hard lockups on cpu 0; > > magic-sysrq-key doesn't work, but tasks on other cpus still apparently > > run. The card runs in the USB 2.0 (480M) mode. > > Did you try this with any other USB2 high-speed sound card, a DVB > receiver, a webcam or hardware like USB sticks or external HDDs? The > device uses isochronous transfers, and the driver doesn't do anything > fancy with it, so it would help a lot to know whether other > hardware/drivers are also affected. USB mass storage works okay, but none of other devices I have probably uses isochronous transfers. > Next thing to try would be whether it makes any difference if you > never queue any outbound URBs (in sound/usb/caiaq/audio.c). Yup, that prevents lockups (and playback, obviously). IMO the bug lies in xhci, so I'll stop CCing you. (I only CCed you originally in case you had a xhci controller to test out) Regards, Matěj -- 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