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.
[akpm@linux-foundation.org: fix CONFIG_CMA=n warning]
[sfr@canb.auug.org.au: better checks before using hugetlb_cma]
Link: http://lkml.kernel.org/r/20200721205716.6dbaa56b@canb.auug.org.au
Fixes: cf11e85fc08c ("mm: hugetlb: optionally allocate gigantic hugepages using cma")
Signed-off-by: Barry Song <song.bao.hua@hisilicon.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Acked-by: Roman Gushchin <guro@fb.com>
Cc: Jonathan Cameron <jonathan.cameron@huawei.com>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/20200710005726.36068-1-song.bao.hua@hisilicon.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index fab4485..590111e 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -45,7 +45,10 @@ int hugetlb_max_hstate __read_mostly;
unsigned int default_hstate_idx;
struct hstate hstates[HUGE_MAX_HSTATE];
+#ifdef CONFIG_CMA
static struct cma *hugetlb_cma[MAX_NUMNODES];
+#endif
+static unsigned long hugetlb_cma_size __initdata;
/*
* Minimum page order among possible hugepage sizes, set to a proper value
@@ -1235,9 +1238,10 @@ static void free_gigantic_page(struct page *page, unsigned int order)
* If the page isn't allocated using the cma allocator,
* cma_release() returns false.
*/
- if (IS_ENABLED(CONFIG_CMA) &&
- cma_release(hugetlb_cma[page_to_nid(page)], page, 1 << order))
+#ifdef CONFIG_CMA
+ if (cma_release(hugetlb_cma[page_to_nid(page)], page, 1 << order))
return;
+#endif
free_contig_range(page_to_pfn(page), 1 << order);
}
@@ -1248,7 +1252,8 @@ static struct page *alloc_gigantic_page(struct hstate *h, gfp_t gfp_mask,
{
unsigned long nr_pages = 1UL << huge_page_order(h);
- if (IS_ENABLED(CONFIG_CMA)) {
+#ifdef CONFIG_CMA
+ {
struct page *page;
int node;
@@ -1262,6 +1267,7 @@ static struct page *alloc_gigantic_page(struct hstate *h, gfp_t gfp_mask,
return page;
}
}
+#endif
return alloc_contig_pages(nr_pages, gfp_mask, nid, nodemask);
}
@@ -2571,7 +2577,7 @@ 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 +5660,6 @@ 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)