I have tried to increase /proc/sys/kernel/watchdog_thresh to 60 but it still not work. I cannot find the full log because every time this stuck happens I must plug-off the power cable. I use Ubuntu 18.04.4
I have had the same issue with stock 18.04 kernels, the 19.10 kernel, and the upboard kernel from the ppa: Linux upboard 5.0.0-1-generic #2~upboard5-Ubuntu
In all cases, reboot/shutdown hangs with the same messages you see.
Hi @AchmadFathoni and @chris_yokum
Thanks for reporting the issue and the additional details on other kernels having the same.
We will investigate it further and come back to you.
'Hang on shutdown or reboot with certain releases. This is a problem related to kernel modules for HSUART DMA support that get loaded. The HSUARTs on the SOC are not normally used on the AtomicPi, however they do appear on the 26pin connector. The HSUARTs can still be used in PIO mode even after disabling DMA support, but will be less CPU efficient. To permanently prevent the modules from loading, edit the file /etc/modprobe.d/blacklist.conf and add lines to the bottom... "
install dw_dmac /bin/true
install dw_dmac_core /bin/true
Any updates on this? I still have this problem with the stock 18.04 kernel and the UP custom 5.0.0 kernel.
Up board hangs on reboot / shutdown.