tree 2851b38cbb8e223d23a35b7150e5071edaeaabe1
parent 3ea277194daaeaa84ce75180ec7c7a2075027a68
author Mike Rapoport <rppt@linux.vnet.ibm.com> 1501705915 -0700
committer Linus Torvalds <torvalds@linux-foundation.org> 1501716886 -0700

userfaultfd: non-cooperative: notify about unmap of destination during mremap

When mremap is called with MREMAP_FIXED it unmaps memory at the
destination address without notifying userfaultfd monitor.

If the destination were registered with userfaultfd, the monitor has no
way to distinguish between the old and new ranges and to properly relate
the page faults that would occur in the destination region.

Fixes: 897ab3e0c49e ("userfaultfd: non-cooperative: add event for memory unmaps")
Link: http://lkml.kernel.org/r/1500276876-3350-1-git-send-email-rppt@linux.vnet.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Acked-by: Pavel Emelyanov <xemul@virtuozzo.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>