From: Mika Penttilä <mpenttil@redhat.com>

With the unified HMM/migrate_device page table walk
migrate_device needs HMM enabled and HMM needs
MMU notifiers. Enable them explicitly to avoid
breaking random configs.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: David Hildenbrand <david@kernel.org>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: "Liam R. Howlett" <Liam.Howlett@oracle.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Mika Penttilä <mpenttil@redhat.com>
---
 mm/Kconfig | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/mm/Kconfig b/mm/Kconfig
index a992f2203eb9..1b8778f34922 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -661,6 +661,7 @@ config MIGRATION
 
 config DEVICE_MIGRATION
 	def_bool MIGRATION && ZONE_DEVICE
+	select HMM_MIRROR
 
 config ARCH_ENABLE_HUGEPAGE_MIGRATION
 	bool
@@ -1236,6 +1237,7 @@ config ZONE_DEVICE
 config HMM_MIRROR
 	bool
 	depends on MMU
+	select MMU_NOTIFIER
 
 config GET_FREE_REGION
 	bool
-- 
2.50.0