  We present updated studies on the chiral phase transition in $N_{f}=2+1$ QCD.
Simulations have been carried out using Highly Improved Staggered Quarks (HISQ)
on lattices with temporal extent $N_{\tau} = 6$ at vanishing baryon chemical
potential. We updated our previous study \cite{Ding:2015pmg} by extending the
temperature window from (140 MeV, 150 MeV) to (140 MeV, 170 MeV). The strange
quark mass was chosen to its physical value $m_{s}^{\mathrm{phy}}$, and five
values of two degenerate light quark masses are varied from
$m_{s}^{\mathrm{phy}}/80$ to $m_{s}^{\mathrm{phy}}/20$ which correspond to a
Goldstone pion mass ranging from 80 MeV to 160 MeV in the continuum limit. The
universal scaling behaviour of the QCD chiral phase transition is investigated
by studying the temperature and quark mass dependences of chiral condensates
and chiral susceptibilities. The window of criticality compared to previous
studies is also discussed.
