I think that I can't use a shared memory with my embedded system (nucleo-144), because I can't see the CONFIG_BUILD_KERNEL=y in my .config file.
You can use "shared memory" in other build modes too. The APIs to management shared memory don't exist in other build modes because they are used only to set the MMU. If there is no MMU, there can be no kernel mode and no /true /shared memory.
But in other build modes ALL memory is shared. A FLAT memory model means that all memory is linearly addressed and, generally, has no protection. So you can use "shared memory" without CONFIG_BUILD_KERNEL=y, you just can't use the APIs to control it. You can create user "shared memory" with malloc() and destroy it with free().
