[PATCH] hugetlb: fix linked list corruption in unmap_hugepage_range()
commit fe1668ae5bf0145014c71797febd9ad5670d5d05 causes kernel to oops with
libhugetlbfs test suite. The problem is that hugetlb pages can be shared
by multiple mappings. Multiple threads can fight over page->lru in the
unmap path and bad things happen. We now serialize __unmap_hugepage_range
to void concurrent linked list manipulation. Such serialization is also
needed for shared page table page on hugetlb area. This patch will fixed
the bug and also serve as a prepatch for shared page table.
Signed-off-by: Ken Chen <kenneth.w.chen@intel.com>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c
index 5e03b2f..4ee3f00 100644
--- a/fs/hugetlbfs/inode.c
+++ b/fs/hugetlbfs/inode.c
@@ -293,7 +293,7 @@
if (h_vm_pgoff >= h_pgoff)
v_offset = 0;
- unmap_hugepage_range(vma,
+ __unmap_hugepage_range(vma,
vma->vm_start + v_offset, vma->vm_end);
}
}