[PATCH v4 07/16] KVM: selftests: Compute number of extra pages needed in mmu_stress_test

Sean Christopherson
2024-11-28T01:03:54Z

Create mmu_stress_tests's VM with the correct number of extra pages needed
to map all of memory in the guest. The bug hasn't been noticed before as
the test currently runs only on x86, which maps guest memory with 1GiB
pages, i.e. doesn't need much memory in the guest for page tables.

Reviewed-by: James Houghton <jthoughton@google.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
---
tools/testing/selftests/kvm/mmu_stress_test.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/tools/testing/selftests/kvm/mmu_stress_test.c b/tools/testing/selftests/kvm/mmu_stress_test.c
index 847da23ec1b1..5467b12f5903 100644
--- a/tools/testing/selftests/kvm/mmu_stress_test.c
+++ b/tools/testing/selftests/kvm/mmu_stress_test.c
@@ -209,7 +209,13 @@ int main(int argc, char *argv[])
vcpus = malloc(nr_vcpus * sizeof(*vcpus));
TEST_ASSERT(vcpus, "Failed to allocate vCPU array");

- vm = vm_create_with_vcpus(nr_vcpus, guest_code, vcpus);
+ vm = __vm_create_with_vcpus(VM_SHAPE_DEFAULT, nr_vcpus,
+#ifdef __x86_64__
+ max_mem / SZ_1G,
+#else
+ max_mem / vm_guest_mode_params[VM_MODE_DEFAULT].page_size,
+#endif
+ guest_code, vcpus);

max_gpa = vm->max_gfn << vm->page_shift;
TEST_ASSERT(max_gpa > (4 * slot_size), "MAXPHYADDR <4gb ");