Error message
xillybus: Failed to close file. Hardware left in messy state.Meaning
This fatal error condition occurs when the driver failed to close a device file as a result of a software signal (CTRL-C or other). Normally, there is no reason closing a file should take any significant amount of time, so the appearance of this error is very likely to indicate a faulty condition on the FPGA, such as a reconfiguration while the device file was opened.
The FPGA didn't get an indication that the file was closed, so there is a loss of sync between the driver and FPGA. Several other errors may be a result of this condition.
Recommended action
This error should be reported, if it's verified that the FPGA was stable since powerup.
To get Xillybus working again, power the computer off, reconfigure the FPGA and power the computer on again.