Re: [PATCH] hugetlbfs: remove call to huge_pte_alloc without i_mmap_rwsem

[Matthew Wilcox]

On Mon, Aug 03, 2020 at 03:43:35PM -0700, Mike Kravetz wrote:
> Commit c0d0381ade79 ("hugetlbfs: use i_mmap_rwsem for more pmd sharing
> synchronization") requires callers of huge_pte_alloc to hold i_mmap_rwsem
> in at least read mode.  This is because the explicit locking in
> huge_pmd_share (called by huge_pte_alloc) was removed.  When restructuring
> the code, the call to huge_pte_alloc in the else block at the beginning
> of hugetlb_fault was missed.

Should we have a call to mmap_assert_locked() in huge_pte_alloc(),
at least the generic one?