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 CRhc+CE6 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nested s390x VM on 2 cpus. >>> >>> I guess I'll really need more info about your specific .config and >>> command line args to help further. > > On s390 cpumask_set_cpu(0, mm_cpumask(&init_mm)); in arch_mm_preinit() writes > out-of-bounds into swap_attrs[] overwriting the terminating NULL. > > This seems to happen because the return value of get_rss_stat_items_size() is > larger than PERCPU_COUNTER_TREE_ITEMS_STATIC_SIZE: > > PERCPU_COUNTER_TREE_ITEMS_STATIC_SIZE: 18688 > get_rss_stat_items_size(): 21504 > > Here I stopped looking further into this. I guess you will figure out > immediately what's wrong :) Indeed! So in get_rss_stat_items_size() we have: static inline size_t get_rss_stat_items_size(void) { return percpu_counter_tree_items_size() * NR_MM_COUNTERS; } And just above: #define MM_STRUCT_FLEXIBLE_ARRAY_INIT \ { \ [0 ... PERCPU_COUNTER_TREE_ITEMS_STATIC_SIZE + sizeof(cpumask_t) + MM_CID_STATIC_SIZE - 1] = 0 \ } Which fails to account for NR_MM_COUNTERS. Does the following fix your issue ? #define MM_STRUCT_FLEXIBLE_ARRAY_INIT \ { \ [0 ... (PERCPU_COUNTER_TREE_ITEMS_STATIC_SIZE * NR_MM_COUNTERS) + sizeof(cpumask_t) + MM_CID_STATIC_SIZE - 1] = 0 \ } It would only cause issues when nr_cpu_ids grows closer to NR_CPUS, which explains why I could not reproduce it locally. Thanks, Mathieu -- Mathieu Desnoyers EfficiOS Inc. https://www.efficios.com