// SPDX-License-Identifier: GPL-2.0-only #include "test_util.h" #include "kvm_util.h" #include "processor.h" #include "vmx.h" #include <string.h> #include <sys/ioctl.h> #include "kselftest.h" #define ARBITRARY_IO_PORT 0x2000 static struct kvm_vm *vm; static void l2_guest_code(void) { /* * Generate an exit to L0 userspace, i.e. main(), via I/O to an * arbitrary port. */ asm volatile("inb %%dx, %%al" : : [port] "d" (ARBITRARY_IO_PORT) : "rax"); } static void l1_guest_code(struct vmx_pages *vmx_pages) { #define L2_GUEST_STACK_SIZE 64 unsigned long l2_guest_stack[L2_GUEST_STACK_SIZE]; GUEST_ASSERT(prepare_for_vmx_operation(vmx_pages)); GUEST_ASSERT(load_vmcs(vmx_pages)); /* Prepare the VMCS for L2 execution. */ prepare_vmcs(vmx_pages, l2_guest_code, &l2_guest_stack[L2_GUEST_STACK_SIZE]); /* * L2 must be run without unrestricted guest, verify that the selftests * library hasn't enabled it. Because KVM selftests jump directly to * 64-bit mode, unrestricted guest support isn't required. */ GUEST_ASSERT(!(vmreadz(CPU_BASED_VM_EXEC_CONTROL) & CPU_BASED_ACTIVATE_SECONDARY_CONTROLS) || !(vmreadz(SECONDARY_VM_EXEC_CONTROL) & SECONDARY_EXEC_UNRESTRICTED_GUEST)); GUEST_ASSERT(!vmlaunch()); /* L2 should triple fault after main() stuffs invalid guest state. */ GUEST_ASSERT(vmreadz(VM_EXIT_REASON) == EXIT_REASON_TRIPLE_FAULT); GUEST_DONE(); } int main(int argc, char *argv[]) { vm_vaddr_t vmx_pages_gva; struct kvm_sregs sregs; struct kvm_vcpu *vcpu; struct kvm_run *run; struct ucall uc; TEST_REQUIRE(kvm_cpu_has(X86_FEATURE_VMX)); vm = vm_create_with_one_vcpu(&vcpu, l1_guest_code); /* Allocate VMX pages and shared descriptors (vmx_pages). */ vcpu_alloc_vmx(vm, &vmx_pages_gva); vcpu_args_set(vcpu, 1, vmx_pages_gva); vcpu_run(vcpu); run = vcpu->run; /* * The first exit to L0 userspace should be an I/O access from L2. * Running L1 should launch L2 without triggering an exit to userspace. */ TEST_ASSERT_KVM_EXIT_REASON(vcpu, KVM_EXIT_IO); TEST_ASSERT(run->io.port == ARBITRARY_IO_PORT, "Expected IN from port %d from L2, got port %d", ARBITRARY_IO_PORT, run->io.port); /* * Stuff invalid guest state for L2 by making TR unusuable. The next * KVM_RUN should induce a TRIPLE_FAULT in L2 as KVM doesn't support * emulating invalid guest state for L2. */ memset(&sregs, 0, sizeof(sregs)); vcpu_sregs_get(vcpu, &sregs); sregs.tr.unusable = 1; vcpu_sregs_set(vcpu, &sregs); vcpu_run(vcpu); switch (get_ucall(vcpu, &uc)) { case UCALL_DONE: break; case UCALL_ABORT: REPORT_GUEST_ASSERT(uc); default: TEST_FAIL("Unexpected ucall: %lu", uc.cmd); } }