  Any modification on gravity would affect not only gravitational wave (GW)
generation but also GW propagation. Therefore, tests of general relativity (GR)
with only GW generation or GW propagation will lead to an overestimate for
deviations. Here we try to use one set of parameters to parameterize the
modifications on both GW generation and GW propagation and then test GR with
GW150914. In our simplest case, we find that graviton mass
$\mu<6.3\times10^{-23}{\rm eV/c^2}$ at $90\%$ C.L. and there are no deviations
from GR at $90\%$ C.L..
