thp: prepare change_huge_pmd() for file thp

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.

Link: http://lkml.kernel.org/r/1466021202-61880-18-git-send-email-kirill.shutemov@linux.intel.com
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Kirill A. Shutemov 2016-07-26 15:25:45 -07:00 committed by Linus Torvalds
parent 628d47ce98
commit b237aded41
1 changed files with 2 additions and 1 deletions

View File

@ -1788,7 +1788,8 @@ 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);
}