kvm: selftests: add svm nested shutdown test

Add test that tests that on SVM if L1 doesn't intercept SHUTDOWN,
then L2 crashes L1 and doesn't crash L2

Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20221103141351.50662-7-mlevitsk@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/tools/testing/selftests/kvm/.gitignore b/tools/testing/selftests/kvm/.gitignore
index 2f0d705..05d980f 100644 (file)
--- a/tools/testing/selftests/kvm/.gitignore
+++ b/tools/testing/selftests/kvm/.gitignore
@@ -41,6 +41,7 @@
 /x86_64/svm_vmcall_test
 /x86_64/svm_int_ctl_test
 /x86_64/svm_nested_soft_inject_test
+/x86_64/svm_nested_shutdown_test
 /x86_64/sync_regs_test
 /x86_64/tsc_msrs_test
 /x86_64/tsc_scaling_sync

diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile
index 0172eb6..4a2caef 100644 (file)
--- a/tools/testing/selftests/kvm/Makefile
+++ b/tools/testing/selftests/kvm/Makefile
@@ -101,6 +101,7 @@ TEST_GEN_PROGS_x86_64 += x86_64/state_test
 TEST_GEN_PROGS_x86_64 += x86_64/vmx_preemption_timer_test
 TEST_GEN_PROGS_x86_64 += x86_64/svm_vmcall_test
 TEST_GEN_PROGS_x86_64 += x86_64/svm_int_ctl_test
+TEST_GEN_PROGS_x86_64 += x86_64/svm_nested_shutdown_test
 TEST_GEN_PROGS_x86_64 += x86_64/svm_nested_soft_inject_test
 TEST_GEN_PROGS_x86_64 += x86_64/tsc_scaling_sync
 TEST_GEN_PROGS_x86_64 += x86_64/sync_regs_test

diff --git a/tools/testing/selftests/kvm/x86_64/svm_nested_shutdown_test.c b/tools/testing/selftests/kvm/x86_64/svm_nested_shutdown_test.c
new file mode 100644 (file)
index 0000000..e73fcde
--- /dev/null
+++ b/tools/testing/selftests/kvm/x86_64/svm_nested_shutdown_test.c
@@ -0,0 +1,67 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * svm_nested_shutdown_test
+ *
+ * Copyright (C) 2022, Red Hat, Inc.
+ *
+ * Nested SVM testing: test that unintercepted shutdown in L2 doesn't crash the host
+ */
+
+#include "test_util.h"
+#include "kvm_util.h"
+#include "processor.h"
+#include "svm_util.h"
+
+static void l2_guest_code(struct svm_test_data *svm)
+{
+       __asm__ __volatile__("ud2");
+}
+
+static void l1_guest_code(struct svm_test_data *svm, struct idt_entry *idt)
+{
+       #define L2_GUEST_STACK_SIZE 64
+       unsigned long l2_guest_stack[L2_GUEST_STACK_SIZE];
+       struct vmcb *vmcb = svm->vmcb;
+
+       generic_svm_setup(svm, l2_guest_code,
+                         &l2_guest_stack[L2_GUEST_STACK_SIZE]);
+
+       vmcb->control.intercept &= ~(BIT(INTERCEPT_SHUTDOWN));
+
+       idt[6].p   = 0; // #UD is intercepted but its injection will cause #NP
+       idt[11].p  = 0; // #NP is not intercepted and will cause another
+                       // #NP that will be converted to #DF
+       idt[8].p   = 0; // #DF will cause #NP which will cause SHUTDOWN
+
+       run_guest(vmcb, svm->vmcb_gpa);
+
+       /* should not reach here */
+       GUEST_ASSERT(0);
+}
+
+int main(int argc, char *argv[])
+{
+       struct kvm_vcpu *vcpu;
+       struct kvm_run *run;
+       vm_vaddr_t svm_gva;
+       struct kvm_vm *vm;
+
+       TEST_REQUIRE(kvm_cpu_has(X86_FEATURE_SVM));
+
+       vm = vm_create_with_one_vcpu(&vcpu, l1_guest_code);
+       vm_init_descriptor_tables(vm);
+       vcpu_init_descriptor_tables(vcpu);
+
+       vcpu_alloc_svm(vm, &svm_gva);
+
+       vcpu_args_set(vcpu, 2, svm_gva, vm->idt);
+       run = vcpu->run;
+
+       vcpu_run(vcpu);
+       TEST_ASSERT(run->exit_reason == KVM_EXIT_SHUTDOWN,
+                   "Got exit_reason other than KVM_EXIT_SHUTDOWN: %u (%s)\n",
+                   run->exit_reason,
+                   exit_reason_str(run->exit_reason));
+
+       kvm_vm_free(vm);
+}