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.

[[email protected]: v4]
  Link: https://lkml.kernel.org/r/[email protected]
Link: https://lkml.kernel.org/r/[email protected]
Link: https://lkml.kernel.org/r/[email protected]
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 <[email protected]>
Suggested-by: David Hildenbrand <[email protected]>
Reviewed-by: Baolin Wang <[email protected]>
Reviewed-by: Kefeng Wang <[email protected]>
Reviewed-by: Davidlohr Bueso <[email protected]>
Reviewed-by: Mike Kravetz <[email protected]>
Acked-by: David Hildenbrand <[email protected]>
Cc: Zhenguo Yao <[email protected]>
Cc: Muchun Song <[email protected]>
Cc: Liu Yuntao <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

0 files changed, 0 insertions, 0 deletions