Disabling CONFIG_SERIAL_8250 in the kernel brakes sysupgrade

Hi there,

I would like to disable CONFIG_SERIAL_8250 in the kernel. But once it is disabled the sysupgrade stops working.
I came across https://openwrt.org/docs/guide-user/additional-software/saving_space, where it mentions that by disabling the kernel setting: This will also save RAM by preventing /sbin/askfirst from running. However, this will break sysupgrade.

But it doesn't explain why it brakes sysupgrade. Is there a way to disable the kernel setting and have working sysupgrade?


Likely not, given the situation you describe. You would need to debug sysupgrade and figure out why and how it breaks. Maybe it is hanging trying to write some informational message to the tty which is not present.