The patch titled Subject: mm/hugetlb: avoid hardcoding while checking if cma is enabled has been added to the -mm tree. Its filename is mm-hugetlb-avoid-hardcoding-while-checking-if-cma-is-enabled.patch This patch should soon appear at http://ozlabs.org/~akpm/mmots/broken-out/mm-hugetlb-avoid-hardcoding-while-checking-if-cma-is-enabled.patch and later at http://ozlabs.org/~akpm/mmotm/broken-out/mm-hugetlb-avoid-hardcoding-while-checking-if-cma-is-enabled.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Barry Song <song.bao.hua@xxxxxxxxxxxxx> Subject: mm/hugetlb: avoid hardcoding while checking if cma is enabled 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. Link: http://lkml.kernel.org/r/20200710005726.36068-1-song.bao.hua@xxxxxxxxxxxxx Fixes: cf11e85fc08c ("mm: hugetlb: optionally allocate gigantic hugepages using cma") Signed-off-by: Barry Song <song.bao.hua@xxxxxxxxxxxxx> Acked-by: Roman Gushchin <guro@xxxxxx> Reviewed-by: Mike Kravetz <mike.kravetz@xxxxxxxxxx> Cc: Jonathan Cameron <jonathan.cameron@xxxxxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/hugetlb.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/mm/hugetlb.c~mm-hugetlb-avoid-hardcoding-while-checking-if-cma-is-enabled +++ a/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_ 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 *old } #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) _ Patches currently in -mm which might be from song.bao.hua@xxxxxxxxxxxxx are mm-hugetlb-avoid-hardcoding-while-checking-if-cma-is-enabled.patch mm-hugetlb-split-hugetlb_cma-in-nodes-with-memory.patch mm-cma-fix-the-name-of-cma-areas.patch mm-hugetlb-fix-the-name-of-hugetlb-cma.patch