Re: [PATCH v1] mm: thp: check pmd_trans_unstable() after split_huge_pmd()

From: Kirill A. Shutemov
Date: Wed Jun 01 2016 - 05:40:10 EST

On Wed, Jun 01, 2016 at 09:36:40AM +0900, Naoya Horiguchi wrote:
> split_huge_pmd() doesn't guarantee that the pmd is normal pmd pointing to
> pte entries, which can be checked with pmd_trans_unstable().

Could you be more specific on when we don't have normal ptes after
split_huge_pmd? Race with other thread? DAX?

I guess we can modify split_huge_pmd() to return if the pmd was split or

Kirill A. Shutemov