On 2022/4/15 13:41, Kefeng Wang wrote:
On 2022/4/15 10:09, Davidlohr Bueso wrote:
On Wed, 13 Apr 2022, Peng Liu wrote:This one should be unnecessary, and this patch looks has a bug,
Certain systems are designed to have sparse/discontiguous nodes. In
this case, nr_online_nodes can not be used to walk through numa node.
Also, a valid node may be greater than nr_online_nodes.
However, in hugetlb, it is assumed that nodes are contiguous. Recheck
all the places that use nr_online_nodes, and repair them one by one.
Suggested-by: David Hildenbrand <david@xxxxxxxxxx>
Fixes: 4178158ef8ca ("hugetlbfs: fix issue of preallocation of gigantic pages can't work")
Fixes: b5389086ad7b ("hugetlbfs: extend the definition of hugepages parameter to support node allocation")
Fixes: e79ce9832316 ("hugetlbfs: fix a truncation issue in hugepages parameter")
Fixes: f9317f77a6e0 ("hugetlb: clean up potential spectre issue warnings")
Signed-off-by: Peng Liu <liupeng256@xxxxxxxxxx>
Reviewed-by: Baolin Wang <baolin.wang@xxxxxxxxxxxxxxxxx>
Reviewed-by: Mike Kravetz <mike.kravetz@xxxxxxxxxx>
Reviewed-by: Davidlohr Bueso <dave@xxxxxxxxxxxx>
... but
---
mm/hugetlb.c | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index b34f50156f7e..5b5a2a5a742f 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -2979,7 +2979,7 @@ int __alloc_bootmem_huge_page(struct hstate *h, int nid)
struct huge_bootmem_page *m = NULL; /* initialize for clang */
int nr_nodes, node;
- if (nid != NUMA_NO_NODE && nid >= nr_online_nodes)
+ if (nid != NUMA_NO_NODE && !node_online(nid))
afaict null_blk could also use this, actually the whole thing wants a
helper - node_valid()?
if a very nid passed to node_online(), it may crash, could you re-check it,
see my changes below,
1) add tmp check against MAX_NUMNODES before node_online() check,
and move it after get tmp in hugepages_setup() , this could cover both per-node alloc and normal alloc
2) due to for_each_online_node() usage, we can drop additional check of nid in __alloc_bootmem_huge_page()
$ git diff
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index fb5a549169ce..5a3ddec181a0 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -2986,8 +2986,6 @@ int __alloc_bootmem_huge_page(struct hstate *h, int nid)
struct huge_bootmem_page *m = NULL; /* initialize for clang */
int nr_nodes, node;
- if (nid != NUMA_NO_NODE && nid >= nr_online_nodes)
- return 0;
/* do node specific alloc */
if (nid != NUMA_NO_NODE) {
m = memblock_alloc_try_nid_raw(huge_page_size(h), huge_page_size(h),
@@ -3095,7 +3093,7 @@ static void __init hugetlb_hstate_alloc_pages(struct hstate *h)
}
/* do node specific alloc */
- for (i = 0; i < nr_online_nodes; i++) {
+ for_each_online_node(i) {
if (h->max_huge_pages_node[i] > 0) {
hugetlb_hstate_alloc_pages_onenode(h, i);
node_specific_alloc = true;
@@ -4059,7 +4057,7 @@ static int __init hugetlb_init(void)
default_hstate.max_huge_pages =
default_hstate_max_huge_pages;
- for (i = 0; i < nr_online_nodes; i++)
+ for_each_online_node(i)
default_hstate.max_huge_pages_node[i] =
default_hugepages_in_node[i];
}
@@ -4168,15 +4166,15 @@ static int __init hugepages_setup(char *s)
count = 0;
if (sscanf(p, "%lu%n", &tmp, &count) != 1)
goto invalid;
+ if (tmp > MAX_NUMNODES || !node_online(tmp))
+ goto invalid;
/* Parameter is node format */
if (p[count] == ':') {
if (!hugetlb_node_alloc_supported()) {
pr_warn("HugeTLB: architecture can't support node specific alloc, ignoring!\n");
return 0;
}
- if (tmp >= nr_online_nodes)
- goto invalid;
- node = array_index_nospec(tmp, nr_online_nodes);
+ node = array_index_nospec(tmp, MAX_NUMNODES);
p += count + 1;
/* Parse hugepages */
if (sscanf(p, "%lu%n", &tmp, &count) != 1)
@@ -4304,7 +4302,7 @@ static int __init default_hugepagesz_setup(char *s)
*/
if (default_hstate_max_huge_pages) {
default_hstate.max_huge_pages = default_hstate_max_huge_pages;
- for (i = 0; i < nr_online_nodes; i++)
+ for_each_online_node(i)
default_hstate.max_huge_pages_node[i] =
default_hugepages_in_node[i];
if (hstate_is_gigantic(&default_hstate))
Yes, node_online is not a safe function which will cause panic if a very big number nid is received. So, this patch needs to be modified. Thanks.
