We register a callback using select_attach on a file descriptor for /dev/ser1 with the SELECT_FLAG_READ and 
SELECT_FLAG_REARM flags and we're occasionally seeing cases where our callback is called and read() returns 0 bytes. 
Once this 0 byte read happens, a kernel trace shows the system going into a tight loop of ionotify, read 0 bytes, 
ionotify, read 0 bytes, etc.. Any ideas what could be causing devc-ser8250 to fire the callback when no data is actually
 pending? Thanks.

Mark