diff options
author | Peter Xu <peterx@redhat.com> | 2022-12-16 18:52:26 +0300 |
---|---|---|
committer | Andrew Morton <akpm@linux-foundation.org> | 2023-01-19 04:12:39 +0300 |
commit | dd361e5033cf36c51acab996ea17748b81cedb38 (patch) | |
tree | 5b3eccbb296ae07feecfdfe622c6e051689308b3 /mm/pagewalk.c | |
parent | eefc7fa53608920203a1402ecf7255ecfa8bb030 (diff) | |
download | linux-dd361e5033cf36c51acab996ea17748b81cedb38.tar.xz |
mm/hugetlb: make walk_hugetlb_range() safe to pmd unshare
Since walk_hugetlb_range() walks the pgtable, it needs the vma lock to
make sure the pgtable page will not be freed concurrently.
Link: https://lkml.kernel.org/r/20221216155226.2043738-1-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: John Hubbard <jhubbard@nvidia.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: James Houghton <jthoughton@google.com>
Cc: Jann Horn <jannh@google.com>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Nadav Amit <nadav.amit@gmail.com>
Cc: Rik van Riel <riel@surriel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'mm/pagewalk.c')
-rw-r--r-- | mm/pagewalk.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/mm/pagewalk.c b/mm/pagewalk.c index 7f1c9b274906..d98564a7be57 100644 --- a/mm/pagewalk.c +++ b/mm/pagewalk.c @@ -302,6 +302,7 @@ static int walk_hugetlb_range(unsigned long addr, unsigned long end, const struct mm_walk_ops *ops = walk->ops; int err = 0; + hugetlb_vma_lock_read(vma); do { next = hugetlb_entry_end(h, addr, end); pte = huge_pte_offset(walk->mm, addr & hmask, sz); @@ -314,6 +315,7 @@ static int walk_hugetlb_range(unsigned long addr, unsigned long end, if (err) break; } while (addr = next, addr != end); + hugetlb_vma_unlock_read(vma); return err; } |