From 65f1f57f35e5e833c879a7afb9c862c603695917 Mon Sep 17 00:00:00 2001 From: Sean Christopherson Date: Tue, 11 Jul 2023 16:01:30 -0700 Subject: [PATCH] KVM: selftests: Verify stats fd can be dup()'d and read Expand the binary stats test to verify that a stats fd can be dup()'d and read, to (very) roughly simulate userspace passing around the file. Adding the dup() test is primarily an intermediate step towards verifying that userspace can read VM/vCPU stats before _and_ after userspace closes its copy of the VM fd; the dup() test itself is only mildly interesting. Signed-off-by: Sean Christopherson Message-Id: <20230711230131.648752-7-seanjc@google.com> Signed-off-by: Paolo Bonzini --- tools/testing/selftests/kvm/kvm_binary_stats_test.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/tools/testing/selftests/kvm/kvm_binary_stats_test.c b/tools/testing/selftests/kvm/kvm_binary_stats_test.c index 653f10d8fb7c..5317e27b77d0 100644 --- a/tools/testing/selftests/kvm/kvm_binary_stats_test.c +++ b/tools/testing/selftests/kvm/kvm_binary_stats_test.c @@ -232,17 +232,23 @@ int main(int argc, char *argv[]) } /* - * Check stats read for every VM and vCPU, with a variety of testcases. + * Check stats read for every VM and vCPU, with a variety of flavors. * Note, stats_test() closes the passed in stats fd. */ for (i = 0; i < max_vm; ++i) { + /* + * Verify that creating multiple userspace references to a + * single stats file works and doesn't cause explosions. + */ vm_stats_fds = vm_get_stats_fd(vms[i]); + stats_test(dup(vm_stats_fds)); /* Verify userspace can instantiate multiple stats files. */ stats_test(vm_get_stats_fd(vms[i])); for (j = 0; j < max_vcpu; ++j) { vcpu_stats_fds[j] = vcpu_get_stats_fd(vcpus[i * max_vcpu + j]); + stats_test(dup(vcpu_stats_fds[j])); stats_test(vcpu_get_stats_fd(vcpus[i * max_vcpu + j])); } -- 2.34.1