Hey guys,
I have noticed that in current master there is an osal Layer (https://github.com/lvgl/lvgl/tree/master/src/osal).
Unfortunately I could find anything in the docs yet. Does this mean lvgl v9 will become thread safe ?
thx for your answers. 
LVGL is still not thread safe.
The OSAL layer primarily helps unify different OS implementations (FreeRTOS, pthreads, CMSIS-RTOS, etc.) under a common API within LVGL. It still has to be enabled/configured in lv_conf.h based on your project setup.
When using LVGL from multiple threads/tasks, you should protect non-thread-safe LVGL calls with lv_lock() / lv_unlock() when OSAL support is enabled.
Alternatively, without the built-in OSAL support, you can still implement your own mutex around LVGL calls.