I guess it happens on a BeagleBone Black: do you get a single warning or multiple repeated messages?
Reading the code, that's a one shot spurious event: drivers/usb/musb/musb_core.c::musb_stage0_irq() ... /* During connection as an A-Device, we may see a short * current spikes causing voltage drop, because of cable * and peripheral capacitance combined with vbus draw. * (So: less common with truly self-powered devices, where * vbus doesn't act like a power supply.) * * Such spikes are short; usually less than ~500 usec, max * of ~2 msec. That is, they're not sustained overcurrent * errors, though they're reported using VBUSERROR irqs. * * Workarounds: (a) hardware: use self powered devices. * (b) software: ignore non-repeated VBUS errors. ... and it might not be related to your wifi dongle not working. Does the same wifi usb dongle work on a x86 box? And could you test it against a vivid kernel there? Which kernel module does it pick up? On a 4.2 wily kernel i have a match for that vendor/product id: git grep 148f ... drivers/net/wireless/mediatek/mt7601u/usb.c: { USB_DEVICE(0x148f, 0x7601) }, <--- HERE drivers/net/wireless/mediatek/mt7601u/usb.c: { USB_DEVICE(0x148f, 0x760a) }, drivers/net/wireless/mediatek/mt7601u/usb.c: { USB_DEVICE(0x148f, 0x760b) }, drivers/net/wireless/mediatek/mt7601u/usb.c: { USB_DEVICE(0x148f, 0x760c) }, drivers/net/wireless/mediatek/mt7601u/usb.c: { USB_DEVICE(0x148f, 0x760d) }, drivers/net/wireless/rt2x00/rt2500usb.c: { USB_DEVICE(0x148f, 0x1706) }, drivers/net/wireless/rt2x00/rt2500usb.c: { USB_DEVICE(0x148f, 0x2570) }, drivers/net/wireless/rt2x00/rt2500usb.c: { USB_DEVICE(0x148f, 0x9020) }, drivers/net/wireless/rt2x00/rt2800usb.c: { USB_DEVICE(0x148f, 0x2070) }, drivers/net/wireless/rt2x00/rt2800usb.c: { USB_DEVICE(0x148f, 0x2770) }, drivers/net/wireless/rt2x00/rt2800usb.c: { USB_DEVICE(0x148f, 0x2870) }, drivers/net/wireless/rt2x00/rt2800usb.c: { USB_DEVICE(0x148f, 0x3070) }, drivers/net/wireless/rt2x00/rt2800usb.c: { USB_DEVICE(0x148f, 0x3071) }, drivers/net/wireless/rt2x00/rt2800usb.c: { USB_DEVICE(0x148f, 0x3072) }, drivers/net/wireless/rt2x00/rt2800usb.c: { USB_DEVICE(0x148f, 0x3370) }, drivers/net/wireless/rt2x00/rt2800usb.c: { USB_DEVICE(0x148f, 0x8070) }, drivers/net/wireless/rt2x00/rt2800usb.c: { USB_DEVICE(0x148f, 0x3572) }, drivers/net/wireless/rt2x00/rt2800usb.c: { USB_DEVICE(0x148f, 0xf301) }, drivers/net/wireless/rt2x00/rt2800usb.c: { USB_DEVICE(0x148f, 0x3573) }, drivers/net/wireless/rt2x00/rt2800usb.c: { USB_DEVICE(0x148f, 0x5370) }, drivers/net/wireless/rt2x00/rt2800usb.c: { USB_DEVICE(0x148f, 0x5372) }, drivers/net/wireless/rt2x00/rt2800usb.c: { USB_DEVICE(0x148f, 0x5572) }, drivers/net/wireless/rt2x00/rt2800usb.c: { USB_DEVICE(0x148f, 0xf101) }, drivers/net/wireless/rt2x00/rt73usb.c: { USB_DEVICE(0x148f, 0x9021) }, drivers/net/wireless/rt2x00/rt73usb.c: { USB_DEVICE(0x148f, 0x2573) }, drivers/net/wireless/rt2x00/rt73usb.c: { USB_DEVICE(0x148f, 0x2671) }, while i don't have any match in vivid, and that mediatek driver is completely missing there: drivers/net/wireless/rt2x00/rt2500usb.c: { USB_DEVICE(0x148f, 0x1706) }, drivers/net/wireless/rt2x00/rt2500usb.c: { USB_DEVICE(0x148f, 0x2570) }, drivers/net/wireless/rt2x00/rt2500usb.c: { USB_DEVICE(0x148f, 0x9020) }, drivers/net/wireless/rt2x00/rt2800usb.c: { USB_DEVICE(0x148f, 0x2070) }, drivers/net/wireless/rt2x00/rt2800usb.c: { USB_DEVICE(0x148f, 0x2770) }, drivers/net/wireless/rt2x00/rt2800usb.c: { USB_DEVICE(0x148f, 0x2870) }, drivers/net/wireless/rt2x00/rt2800usb.c: { USB_DEVICE(0x148f, 0x3070) }, drivers/net/wireless/rt2x00/rt2800usb.c: { USB_DEVICE(0x148f, 0x3071) }, drivers/net/wireless/rt2x00/rt2800usb.c: { USB_DEVICE(0x148f, 0x3072) }, drivers/net/wireless/rt2x00/rt2800usb.c: { USB_DEVICE(0x148f, 0x3370) }, drivers/net/wireless/rt2x00/rt2800usb.c: { USB_DEVICE(0x148f, 0x8070) }, drivers/net/wireless/rt2x00/rt2800usb.c: { USB_DEVICE(0x148f, 0x3572) }, drivers/net/wireless/rt2x00/rt2800usb.c: { USB_DEVICE(0x148f, 0xf301) }, drivers/net/wireless/rt2x00/rt2800usb.c: { USB_DEVICE(0x148f, 0x3573) }, drivers/net/wireless/rt2x00/rt2800usb.c: { USB_DEVICE(0x148f, 0x5370) }, drivers/net/wireless/rt2x00/rt2800usb.c: { USB_DEVICE(0x148f, 0x5372) }, drivers/net/wireless/rt2x00/rt2800usb.c: { USB_DEVICE(0x148f, 0x5572) }, drivers/net/wireless/rt2x00/rt2800usb.c: { USB_DEVICE(0x148f, 0xf101) }, drivers/net/wireless/rt2x00/rt73usb.c: { USB_DEVICE(0x148f, 0x9021) }, drivers/net/wireless/rt2x00/rt73usb.c: { USB_DEVICE(0x148f, 0x2573) }, drivers/net/wireless/rt2x00/rt73usb.c: { USB_DEVICE(0x148f, 0x2671) }, -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1491094 Title: wifi USB dongle fails to work with musb-hdrc error Status in Snappy: New Status in linux package in Ubuntu: Incomplete Bug description: Sep 1 19:03:26 localhost kernel: [ 193.893355] musb-hdrc musb-hdrc.1.auto: VBUS_ERROR in a_wait_bcon (89, <AValid), retry #1, port1 00000104 Sep 1 19:03:27 localhost kernel: [ 194.279941] usb 1-1: new high-speed USB device number 2 using musb-hdrc Sep 1 19:03:27 localhost kernel: [ 194.408824] usb 1-1: New USB device found, idVendor=148f, idProduct=7601 Sep 1 19:03:27 localhost kernel: [ 194.408879] usb 1-1: New USB device strings: Mfr=1, Product=2, SerialNumber=3 Sep 1 19:03:27 localhost kernel: [ 194.408914] usb 1-1: Product: Љ Sep 1 19:03:27 localhost kernel: [ 194.408945] usb 1-1: Manufacturer: Љ Sep 1 19:03:27 localhost kernel: [ 194.408977] usb 1-1: SerialNumber: Љ To manage notifications about this bug go to: https://bugs.launchpad.net/snappy/+bug/1491094/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp