Re: [PATCH 05/10] mm/hugetlb: Make userfaultfd_huge_must_wait() safe to pmd unshare

To: Peter Xu <peterx@xxxxxxxxxx>, linux-mm@xxxxxxxxx, linux-kernel@xxxxxxxxxxxxxxx
Subject: Re: [PATCH 05/10] mm/hugetlb: Make userfaultfd_huge_must_wait() safe to pmd unshare
From: David Hildenbrand <david@xxxxxxxxxx>
Date: Wed, 30 Nov 2022 17:08:07 +0100
Cc: James Houghton <jthoughton@xxxxxxxxxx>, Jann Horn <jannh@xxxxxxxxxx>, Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>, Andrea Arcangeli <aarcange@xxxxxxxxxx>, Rik van Riel <riel@xxxxxxxxxxx>, Nadav Amit <nadav.amit@xxxxxxxxx>, Miaohe Lin <linmiaohe@xxxxxxxxxx>, Muchun Song <songmuchun@xxxxxxxxxxxxx>, Mike Kravetz <mike.kravetz@xxxxxxxxxx>
In-reply-to: <20221129193526.3588187-6-peterx@redhat.com>
Organization: Red Hat
References: <20221129193526.3588187-1-peterx@redhat.com> <20221129193526.3588187-6-peterx@redhat.com>
User-agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.5.0

On 29.11.22 20:35, Peter Xu wrote:

We can take the hugetlb walker lock, here taking vma lock directly.

Signed-off-by: Peter Xu <peterx@xxxxxxxxxx>
---


Reviewed-by: David Hildenbrand <david@xxxxxxxxxx>

--
Thanks,

David / dhildenb

References:
- [PATCH 00/10] mm/hugetlb: Make huge_pte_offset() thread-safe for pmd unshare
  - From: Peter Xu
- [PATCH 05/10] mm/hugetlb: Make userfaultfd_huge_must_wait() safe to pmd unshare
  - From: Peter Xu