diff options
| author | Nadav Amit <namit@vmware.com> | 2021-11-21 21:40:08 +0100 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2021-11-22 20:36:46 +0100 |
| commit | 13e4ad2ce8df6e058ef482a31fdd81c725b0f7ea (patch) | |
| tree | f299abe211d8fdb36b2134fc739fbb5880cebacb /mm | |
| parent | hugetlbfs: flush TLBs correctly after huge_pmd_unshare (diff) | |
| download | linux-13e4ad2ce8df6e058ef482a31fdd81c725b0f7ea.tar.xz linux-13e4ad2ce8df6e058ef482a31fdd81c725b0f7ea.zip | |
hugetlbfs: flush before unlock on move_hugetlb_page_tables()
We must flush the TLB before releasing i_mmap_rwsem to avoid the
potential reuse of an unshared PMDs page. This is not true in the case
of move_hugetlb_page_tables(). The last reference on the page table can
therefore be dropped before the TLB flush took place.
Prevent it by reordering the operations and flushing the TLB before
releasing i_mmap_rwsem.
Fixes: 550a7d60bd5e ("mm, hugepages: add mremap() support for hugepage backed vma")
Signed-off-by: Nadav Amit <namit@vmware.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mina Almasry <almasrymina@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/hugetlb.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 2ccebe1ca9f4..abcd1785c629 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -4919,9 +4919,9 @@ int move_hugetlb_page_tables(struct vm_area_struct *vma, move_huge_pte(vma, old_addr, new_addr, src_pte); } - i_mmap_unlock_write(mapping); flush_tlb_range(vma, old_end - len, old_end); mmu_notifier_invalidate_range_end(&range); + i_mmap_unlock_write(mapping); return len + old_addr - old_end; } |