[PATCHv8 12/32] thp: prepare change_huge_pmd() for file thp

Kirill A. Shutemov
2016-05-12T15:49:48Z

change_huge_pmd() has assert which is not relvant for file page.
For shared mapping it's perfectly fine to have page table entry
writable, without explicit mkwrite.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
---
mm/huge_memory.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 6acb64e6ce79..cff5bc64d006 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -1795,7 +1795,8 @@ int change_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
entry = pmd_mkwrite(entry);
ret = HPAGE_PMD_NR;
set_pmd_at(mm, addr, pmd, entry);
- BUG_ON(!preserve_write && pmd_write(entry));
+ BUG_ON(vma_is_anonymous(vma) && !preserve_write &&
+ pmd_write(entry));
}
spin_unlock(ptl);
}
--
2.8.1