Commit 2e35014f authored by Peng Liu's avatar Peng Liu Committed by Liu Shixin
Browse files

hugetlb: fix wrong use of nr_online_nodes

mainline inclusion
from mainline-v5.19-rc1
commit 0a7a0f6f
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I6OWV4
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=0a7a0f6f7f3679c906fc55e3805c1d5e2c566f55

--------------------------------

Patch series "hugetlb: Fix some incorrect behavior", v3.

This series fix three bugs of hugetlb:
1) Invalid use of nr_online_nodes;
2) Inconsistency between 1G hugepage and 2M hugepage;
3) Useless information in dmesg.

This patch (of 4):

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.

For sparse/discontiguous nodes, the current code may treat a valid node
as invalid, and will fail to allocate all hugepages on a valid node that
"nid >= nr_online_nodes".

As David suggested:

	if (tmp >= nr_online_nodes)
		goto invalid;

Just imagine node 0 and node 2 are online, and node 1 is offline.
Assuming that "node < 2" is valid is wrong.

Recheck all the places that use nr_online_nodes, and repair them one by
one.

[liupeng256@huawei.com: v4]
  Link: https://lkml.kernel.org/r/20220416103526.3287348-1-liupeng256@huawei.com
Link: https://lkml.kernel.org/r/20220413032915.251254-1-liupeng256@huawei.com
Link: https://lkml.kernel.org/r/20220413032915.251254-2-liupeng256@huawei.com


Fixes: 4178158e ("hugetlbfs: fix issue of preallocation of gigantic pages can't work")
Fixes: b5389086 ("hugetlbfs: extend the definition of hugepages parameter to support node allocation")
Fixes: e79ce983 ("hugetlbfs: fix a truncation issue in hugepages parameter")
Fixes: f9317f77 ("hugetlb: clean up potential spectre issue warnings")
Signed-off-by: default avatarPeng Liu <liupeng256@huawei.com>
Suggested-by: default avatarDavid Hildenbrand <david@redhat.com>
Reviewed-by: default avatarBaolin Wang <baolin.wang@linux.alibaba.com>
Reviewed-by: default avatarKefeng Wang <wangkefeng.wang@huawei.com>
Reviewed-by: default avatarDavidlohr Bueso <dave@stgolabs.net>
Reviewed-by: default avatarMike Kravetz <mike.kravetz@oracle.com>
Acked-by: default avatarDavid Hildenbrand <david@redhat.com>
Cc: Zhenguo Yao <yaozhenguo1@gmail.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Liu Yuntao <liuyuntao10@huawei.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Conflicts:
	mm/hugetlb.c
Signed-off-by: default avatarLiu Shixin <liushixin2@huawei.com>
parent 5a1d2ec2
Loading
Loading
Loading
Loading
0% Loading or .
You are about to add 0 people to the discussion. Proceed with caution.
Please to comment