hugetlb_cma[0] can be NULL due to various reasons, for example, node0 has no memory. so NULL hugetlb_cma[0] doesn't necessarily mean cma is not enabled. gigantic pages might have been reserved on other nodes. This patch fixes possible double reservation and CMA leak. Fixes: cf11e85fc08c ("mm: hugetlb: optionally allocate gigantic hugepages using cma") Cc: Mike Kravetz <mike.kravetz@xxxxxxxxxx> Cc: Jonathan Cameron <jonathan.cameron@xxxxxxxxxx> Acked-by: Roman Gushchin <guro@xxxxxx> Signed-off-by: Barry Song <song.bao.hua@xxxxxxxxxxxxx> --- v4: address linux-next issue; use hugetlb_cma_size to check if cma is enabled mm/hugetlb.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 57ece74e3aae..bc3304af40d0 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -46,6 +46,7 @@ unsigned int default_hstate_idx; struct hstate hstates[HUGE_MAX_HSTATE]; static struct cma *hugetlb_cma[MAX_NUMNODES]; +static unsigned long hugetlb_cma_size __initdata; /* * Minimum page order among possible hugepage sizes, set to a proper value @@ -2571,7 +2572,7 @@ static void __init hugetlb_hstate_alloc_pages(struct hstate *h) for (i = 0; i < h->max_huge_pages; ++i) { if (hstate_is_gigantic(h)) { - if (IS_ENABLED(CONFIG_CMA) && hugetlb_cma[0]) { + if (hugetlb_cma_size) { pr_warn_once("HugeTLB: hugetlb_cma is enabled, skip boot time allocation\n"); break; } @@ -5654,7 +5655,6 @@ void move_hugetlb_state(struct page *oldpage, struct page *newpage, int reason) } #ifdef CONFIG_CMA -static unsigned long hugetlb_cma_size __initdata; static bool cma_reserve_called __initdata; static int __init cmdline_parse_hugetlb_cma(char *p) -- 2.27.0