Playing with memory_region_is_mapped(), I realized that memory regions
mapped via an alias behave a little bit "differently", as they don't have
their ->container set.
* memory_region_is_mapped() will never succeed for memory regions mapped
  via an alias
* memory_region_to_address_space(), memory_region_find(),
  memory_region_find_rcu(), memory_region_present() won't work, which seems
  okay, because we don't expect such memory regions getting passed to these
  functions.
* memory_region_to_absolute_addr() will result in a wrong address. As
  the result is only used for tracing, that is tolerable.

Let's clarify the documentation of memory_region_is_mapped() and change
one user that really should be checking something else.

Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: Marcel Apfelbaum <marcel.apfelbaum@gmail.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: Richard Henderson <richard.henderson@linaro.org>
Cc: Philippe Mathieu-Daudé <f4bug@amsat.org>

David Hildenbrand (2):
  machine: Use host_memory_backend_is_mapped() in
    machine_consume_memdev()
  memory: Update description of memory_region_is_mapped()

 hw/core/machine.c     | 2 +-
 include/exec/memory.h | 3 ++-
 2 files changed, 3 insertions(+), 2 deletions(-)

-- 
2.31.1