I have a problem my board is blocked for the second time.
But my configuration is quite different:
Kernel: linux-image-next-sunxi 4.3 (version 4.2.0-sunxi)
UBoot: linux-image-next-sunxi 4.3 (2015.07)
RootFS: on sda1 powered by the board (WDC WD10JFCX-68N)
UpTime: about 10 days before my last restart.
When the board is blocked I can't interact with the debug console on the serial port.
I cant't find anything interesting in /var/log, but I'm not really an expert.
Could easily be random (electrical) noise or RFI.
John
Do you have a back-up Li-Po battery attached?