Default logging version has changed!

Chruściński, Krzysztof


Almost a year ago logging subsystem v2 was merged as an optional engine. It has the same user API but backend API has changed (see for details). Legacy logging was still the default one. During last few months all zephyr backends were ported to support both APIs. Yesterday got merged and v2 become the default and v1 is now deprecated (to be removed after v3.1).

For most of the users it should be transparent. However, if you use custom backend that does not support v2 API you can still use v1 (CONFIG_LOG1=y).

If you already were using v2 logging by enabling CONFIG_LOG2_MODE_{IMMEDIATE,DEFERRED}=y you'll notice that those options are now deprecated (cmake warning). Use CONFIG_LOG_MODE_{IMMEDIATE,DEFERRED}=y instead.

Please report any bugs found.


This is the documentation for the latest (main) development branch of Zephyr. If you are looking for the documentation of previous releases, use the drop-down menu on the left and select the desired version.

Counter proposal to #41739. Deprecated CONFIG_LOG2_MODE_DEFERRED and CONFIG_LOG2_MODE_IMMEDIATE. Introduced CONFIG_LOG1 which enables legacy v1 (with cmake warning). CONFIG_LOG_MODE_IMMEDIATE=y and...