Re: kern/56099: USB xHCI panic when using microphone

[sc dying <sc.dying%gmail.com@localhost>]

Does xhci_event_transfer() forget to increment xx_isoc_done and
avoid calling usb_transfer_comeplete() in error paths?
When an error occurs while isoc transfer, i.e. completion code is not
SUCCESS nor SHORT_PKT, usb_transfer_comeplete is called without
incrementing xx_isoc_done and the xfer is removed from up_queue.
Then, usb_transfer_comeplete is called at the last of transferring
ux_frlengths[], but it cannot find the xfer in up_queue and fires KASSERT.