hugetlb: fix wrong use of nr_online_nodes
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:Peng Liu <liupeng256@huawei.com> Suggested-by:
David Hildenbrand <david@redhat.com> Reviewed-by:
Baolin Wang <baolin.wang@linux.alibaba.com> Reviewed-by:
Kefeng Wang <wangkefeng.wang@huawei.com> Reviewed-by:
Davidlohr Bueso <dave@stgolabs.net> Reviewed-by:
Mike Kravetz <mike.kravetz@oracle.com> Acked-by:
David 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:
Andrew Morton <akpm@linux-foundation.org>
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f47f758c
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