The groundwork for missing mmu notifiers seems to already be covered. They just need to add a check for the absence of the __mmu_notifier_register function.
In kernel/nvidia-uvm/uvm_linux.h, change the #define UVM_CAN_USE_MMU_NOTIFIERS() 1 line. Or, for a more “proper” check:
diff --git a/kernel/conftest.sh b/kernel/conftest.sh
index a4ebf81..00d02d9 100755
--- a/kernel/conftest.sh
+++ b/kernel/conftest.sh
@@ -3647,10 +3647,20 @@ compile_test() {
}"
compile_check_conftest "$CODE" "NV_MMU_NOTIFIER_OPS_HAS_INVALIDATE_RANGE" "" "types"
;;
+ __mmu_notifier_register)
+ CODE="
+ #include <linux/mmu_notifier.h>
+ void conftest_mmu_notifier_register(void) {
+ __mmu_notifier_register();
+ }"
+
+ compile_check_conftest "$CODE" "NV_MMU_NOTIFIER_REGISTER" "" "functions"
+ ;;
+
drm_format_num_planes)
#
# Determine if drm_format_num_planes() function is present.
#
# The drm_format_num_planes() function was added by commit
diff --git a/kernel/nvidia-uvm/nvidia-uvm.Kbuild b/kernel/nvidia-uvm/nvidia-uvm.Kbuild
index 0a1a4e9..f052391 100644
--- a/kernel/nvidia-uvm/nvidia-uvm.Kbuild
+++ b/kernel/nvidia-uvm/nvidia-uvm.Kbuild
@@ -97,10 +97,11 @@ NV_CONFTEST_FUNCTION_COMPILE_TESTS += console_lock
NV_CONFTEST_FUNCTION_COMPILE_TESTS += pci_bus_address
NV_CONFTEST_FUNCTION_COMPILE_TESTS += set_memory_uc
NV_CONFTEST_FUNCTION_COMPILE_TESTS += set_pages_uc
NV_CONFTEST_FUNCTION_COMPILE_TESTS += acpi_walk_namespace
NV_CONFTEST_FUNCTION_COMPILE_TESTS += ktime_get_raw_ts64
+NV_CONFTEST_FUNCTION_COMPILE_TESTS += __mmu_notifier_register
NV_CONFTEST_TYPE_COMPILE_TESTS += outer_flush_all
NV_CONFTEST_TYPE_COMPILE_TESTS += file_operations
NV_CONFTEST_TYPE_COMPILE_TESTS += kuid_t
NV_CONFTEST_TYPE_COMPILE_TESTS += address_space
diff --git a/kernel/nvidia-uvm/uvm_linux.h b/kernel/nvidia-uvm/uvm_linux.h
index ef7771d..41d7147 100644
--- a/kernel/nvidia-uvm/uvm_linux.h
+++ b/kernel/nvidia-uvm/uvm_linux.h
@@ -138,11 +138,11 @@ static inline const struct cpumask *uvm_cpumask_of_node(int node)
// after all of the above issues were resolved, so we assume the fixes are
// present if we see the callback.
//
// The callback was added in commit 0f0a327fa12cd55de5e7f8c05a70ac3d047f405e,
// v3.19 (2014-11-13).
-#if defined(NV_MMU_NOTIFIER_OPS_HAS_INVALIDATE_RANGE)
+#if defined(NV_MMU_NOTIFIER_REGISTER) && defined(NV_MMU_NOTIFIER_OPS_HAS_INVALIDATE_RANGE)
#define UVM_CAN_USE_MMU_NOTIFIERS() 1
#else
#define UVM_CAN_USE_MMU_NOTIFIERS() 0
#endif