mm/rmap: fix new bug: premature return from page_mlock_one()

In the unlikely race case that page_mlock_one() finds VM_LOCKED has been
cleared by the time it got page table lock, page_vma_mapped_walk_done()
must be called before returning, either explicitly, or by a final call
to page_vma_mapped_walk() - otherwise the page table remains locked.

Fixes: cd62734ca60d ("mm/rmap: split try_to_munlock from try_to_unmap")
Signed-off-by: Hugh Dickins <[email protected]>
Reviewed-by: Alistair Popple <[email protected]>
Reviewed-by: Shakeel Butt <[email protected]>
Reported-by: kernel test robot <[email protected]>
Link: https://lore.kernel.org/lkml/20210711151446.GB4070@xsang-OptiPlex-9020/
Link: https://lore.kernel.org/lkml/[email protected]/
Cc: Andrew Morton <[email protected]>
Cc: Jason Gunthorpe <[email protected]>
Cc: Ralph Campbell <[email protected]>
Cc: Christoph Hellwig <[email protected]>
Cc: Yang Shi <[email protected]>
Cc: Kirill A. Shutemov <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

0 files changed, 0 insertions, 0 deletions