Boot problem after upgrading to R4.2

I think stage 1 has failed (whonix-ws and debian_2nd templates) during R4.1 → R4.2 upgrade. Later I did cmd line upgrade on dom0 sudo qubes-dom0-update and it has asked to reboot to continue the upgrade.

After the reboot, qubes doesn’t boot up anymore. Getting stuck at the message “[ 4.602791] dracut-cmdline[286]: Warning: USB in dom0 is not restricted. Consider rd.qubes.hide_all_usb or usbcore.authorized default=0.”
After going to “advanced” menu, I managed to view boot messages.

As per screenshot, it just sits there.

Also I noticed after booting into rescue shell via live usb disk and then mounted the EFI partition that xen.cfg is empty.