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You need root access on both machines for these operations. It is also noteworthy that if the remote USB device is disconnected (e.g., because of a FPGA power-cycle) it is necessary to recreate the virtual USB device on the local host. Consult the usbip documentation for details.
XVC
It is also possible to drive JTAG with a firmware core and use the Xilinx XVC protocol to remotely access JTAG. The SLAC surf library provides the necessary components.