linux-kernel - [PATCH v7 10/12] KVM: selftests: cover GUEST_MEMFD_FLAG_NO_DIRECT

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Message-ID: <20250924152214.7292-7-roypat@amazon.co.uk>
Date: Wed, 24 Sep 2025 15:22:47 +0000
From: "Roy, Patrick" <roypat@...zon.co.uk>
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Subject: [PATCH v7 10/12] KVM: selftests: cover GUEST_MEMFD_FLAG_NO_DIRECT_MAP
 in existing selftests

Extend mem conversion selftests to cover the scenario that the guest can
fault in and write gmem-backed guest memory even if its direct map
removed. Also cover the new flag in guest_memfd_test.c tests.

Signed-off-by: Patrick Roy <roypat@...zon.co.uk>
---
 tools/testing/selftests/kvm/guest_memfd_test.c             | 2 ++
 .../selftests/kvm/x86/private_mem_conversions_test.c       | 7 ++++---
 2 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/tools/testing/selftests/kvm/guest_memfd_test.c b/tools/testing/selftests/kvm/guest_memfd_test.c
index b3ca6737f304..1187438b6831 100644
--- a/tools/testing/selftests/kvm/guest_memfd_test.c
+++ b/tools/testing/selftests/kvm/guest_memfd_test.c
@@ -275,6 +275,8 @@ static void test_guest_memfd(unsigned long vm_type)
 
 	if (vm_check_cap(vm, KVM_CAP_GUEST_MEMFD_MMAP))
 		flags |= GUEST_MEMFD_FLAG_MMAP;
+	if (vm_check_cap(vm, KVM_CAP_GUEST_MEMFD_NO_DIRECT_MAP))
+		flags |= GUEST_MEMFD_FLAG_NO_DIRECT_MAP;
 
 	test_create_guest_memfd_multiple(vm);
 	test_create_guest_memfd_invalid_sizes(vm, flags, page_size);
diff --git a/tools/testing/selftests/kvm/x86/private_mem_conversions_test.c b/tools/testing/selftests/kvm/x86/private_mem_conversions_test.c
index 82a8d88b5338..8427d9fbdb23 100644
--- a/tools/testing/selftests/kvm/x86/private_mem_conversions_test.c
+++ b/tools/testing/selftests/kvm/x86/private_mem_conversions_test.c
@@ -367,7 +367,7 @@ static void *__test_mem_conversions(void *__vcpu)
 }
 
 static void test_mem_conversions(enum vm_mem_backing_src_type src_type, uint32_t nr_vcpus,
-				 uint32_t nr_memslots)
+				 uint32_t nr_memslots, uint64_t gmem_flags)
 {
 	/*
 	 * Allocate enough memory so that each vCPU's chunk of memory can be
@@ -394,7 +394,7 @@ static void test_mem_conversions(enum vm_mem_backing_src_type src_type, uint32_t
 
 	vm_enable_cap(vm, KVM_CAP_EXIT_HYPERCALL, (1 << KVM_HC_MAP_GPA_RANGE));
 
-	memfd = vm_create_guest_memfd(vm, memfd_size, 0);
+	memfd = vm_create_guest_memfd(vm, memfd_size, gmem_flags);
 
 	for (i = 0; i < nr_memslots; i++)
 		vm_mem_add(vm, src_type, BASE_DATA_GPA + slot_size * i,
@@ -477,7 +477,8 @@ int main(int argc, char *argv[])
 		}
 	}
 
-	test_mem_conversions(src_type, nr_vcpus, nr_memslots);
+	test_mem_conversions(src_type, nr_vcpus, nr_memslots, 0);
+	test_mem_conversions(src_type, nr_vcpus, nr_memslots, GUEST_MEMFD_FLAG_NO_DIRECT_MAP);
 
 	return 0;
 }
-- 
2.51.0