kmalloc before kmem_cache_init

I am kind of lost trying to figure out how can kmallocs work if they are called before kmem_cache_init (e.g. such a case occurs when in start_kernel() we call parse_early_param() (which in turn might call early_serial8250_setup() if earlycon= is used in kernel command-line) before mm_init()  (which later calls kmem_cache_init() )

From what I understood, kmalloc() (SLUB implementation) first tries to find out the slab fit for the size being kmalloced and slabs are nothing but kmalloc_caches[]. Now these kmalloc_caches get initialized in kmem_cache_init().

What am I missing here ? Regards, Sukanto Ghosh -- Regards, Sukanto Ghosh