diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 2f901a6e13d2..a81f2a8556c8 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -2288,13 +2288,33 @@ found: } #define persistent_huge_pages(h) (h->nr_huge_pages - h->surplus_huge_pages) -static int set_max_huge_pages(struct hstate *h, unsigned long count, +static int set_max_huge_pages(struct hstate *h, unsigned long count, int nid, nodemask_t *nodes_allowed) { unsigned long min_count, ret; spin_lock(&hugetlb_lock); + /* + * Check for a node specific request. + * Changing node specific huge page count may require a corresponding + * change to the global count. In any case, the passed node mask + * (nodes_allowed) will restrict alloc/free to the specified node. + */ + if (nid != NUMA_NO_NODE) { + unsigned long old_count = count; + + count += h->nr_huge_pages - h->nr_huge_pages_node[nid]; + /* + * User may have specified a large count value which caused the + * above calculation to overflow. In this case, they wanted + * to allocate as many huge pages as possible. Set count to + * largest possible value to align with their intention. + */ + if (count < old_count) + count = ULONG_MAX; + } + /* * Gigantic pages runtime allocation depend on the capability for large * page range allocation. @@ -2446,15 +2466,22 @@ static ssize_t __nr_hugepages_store_common(bool obey_mempolicy, } } else if (nodes_allowed) { /* - * per node hstate attribute: adjust count to global, - * but restrict alloc/free to the specified node. + * Node specific request. count adjustment happens in + * set_max_huge_pages() after acquiring hugetlb_lock. */ - count += h->nr_huge_pages - h->nr_huge_pages_node[nid]; init_nodemask_of_node(nodes_allowed, nid); - } else - nodes_allowed = &node_states[N_MEMORY]; + } else { + /* + * Node specific request, but we could not allocate the few + * words required for a node mask. We are unlikely to hit + * this condition. Since we can not pass down the appropriate + * node mask, just return ENOMEM. + */ + err = -ENOMEM; + goto out; + } - err = set_max_huge_pages(h, count, nodes_allowed); + err = set_max_huge_pages(h, count, nid, nodes_allowed); out: if (nodes_allowed != &node_states[N_MEMORY])