On Fri, 2022-05-27 at 17:55 +0530, Aneesh Kumar K.V wrote: [snip] > > +static int __init memory_tier_init(void) > +{ > + int ret; > + > + ret = subsys_system_register(&memory_tier_subsys, memory_tier_attr_groups); > + if (ret) > + panic("%s() failed to register subsystem: %d\n", __func__, ret); I don't think we should go panic for failing to register subsys and device for memory tiers. Just pr_err() should be enough. Best Regards, Huang, Ying > + > + /* > + * Register only default memory tier to hide all empty > + * memory tier from sysfs. > + */ > + ret = register_memory_tier(DEFAULT_MEMORY_TIER); > + if (ret) > + panic("%s() failed to register memory tier: %d\n", __func__, ret); > + > + /* > + * CPU only nodes are not part of memoty tiers. > + */ > + memory_tiers[DEFAULT_MEMORY_TIER]->nodelist = node_states[N_MEMORY]; > + > + return 0; > +} > +subsys_initcall(memory_tier_init); > + > +#endif /* CONFIG_TIERED_MEMORY */