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:
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()?
This one should be unnecessary, and this patch looks has a bug,
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
sorry，for normal alloc, tmp is the number of huge pages, we don't need
the movement, only add tmp >= MAX_NUMNODES is ok
2) due to for_each_online_node() usage, we can drop additional check
of nid in __alloc_bootmem_huge_page()
