// 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);
}
}