On Mon, 12 Oct 2020, Xianting Tian wrote: > In architecture like powerpc, we can have cpus without any local memory > attached to it. In such cases the node does not have real memory. > > In many places of current kernel code, it doesn't judge whether the node is > memoryless numa node before calling allocator interface. That is intentional. SLUB relies on the page allocator to pick a node. > This patch is to use local_memory_node(), which is guaranteed to have > memory, in allocator interface. local_memory_node() is a noop in other > architectures that don't support memoryless nodes. The patch would destroy the support for memory policies in the SLUB allocator and likely in the other ones as well.