rmap: fix compound check logic in page_remove_file_rmap

In page_remove_file_rmap(.) we have the following check:

  VM_BUG_ON_PAGE(compound && !PageTransHuge(page), page);

This is meant to check for either HugeTLB pages or THP when a compound
page is passed in.

Unfortunately, if one disables CONFIG_TRANSPARENT_HUGEPAGE, then
PageTransHuge(.) will always return false, provoking BUGs when one runs
the libhugetlbfs test suite.

This patch replaces PageTransHuge(), with PageHead() which will work for
both HugeTLB and THP.

Fixes: dd78fedde4 ("rmap: support file thp")
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Steve Capper <[email protected]>
Acked-by: Kirill A. Shutemov <[email protected]>
Cc: Huang Shijie <[email protected]>
Cc: Will Deacon <[email protected]>
Cc: Catalin Marinas <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
This commit is contained in:
Steve Capper 2016-08-10 16:27:55 -07:00 • committed by Linus Torvalds
commit 57dea93ac4

View file

@ -1304,7 +1304,7 @@ static void page_remove_file_rmap(struct page *page, bool compound)
{
int i, nr = 1;
VM_BUG_ON_PAGE(compound && !PageTransHuge(page), page);
VM_BUG_ON_PAGE(compound && !PageHead(page), page);
lock_page_memcg(page);
/* Hugepages are not counted in NR_FILE_MAPPED for now. */