[PATCH 064/128] KVM: selftests: Convert userspace_msr_exit_test away from VCPU_ID

Sean Christopherson
2022-05-04T22:53:35Z

Convert userspace_msr_exit_test to use vm_create_with_one_vcpu() and pass
around a 'struct kvm_vcpu' object instead of using a global VCPU_ID.
Note, this is a "functional" change in the sense that the test now
creates a vCPU with vcpu_id==0 instead of vcpu_id==1. The non-zero
VCPU_ID was 100% arbitrary and added little to no validation coverage.
If testing non-zero vCPU IDs is desirable for generic tests, that can be
done in the future by tweaking the VM creation helpers.

Opportunistically use vcpu_run() instead of _vcpu_run() with an open
coded assert that KVM_RUN succeeded. Fix minor coding style violations
too.

Signed-off-by: Sean Christopherson <seanjc@google.com>
---
.../kvm/x86_64/userspace_msr_exit_test.c | 165 +++++++++---------
1 file changed, 78 insertions(+), 87 deletions(-)

diff --git a/tools/testing/selftests/kvm/x86_64/userspace_msr_exit_test.c b/tools/testing/selftests/kvm/x86_64/userspace_msr_exit_test.c
index e3e20e8848d0..e261c50fac5c 100644
--- a/tools/testing/selftests/kvm/x86_64/userspace_msr_exit_test.c
+++ b/tools/testing/selftests/kvm/x86_64/userspace_msr_exit_test.c
@@ -17,7 +17,6 @@
#define KVM_FEP_LENGTH 5
static int fep_available = 1;

-#define VCPU_ID 1
#define MSR_NON_EXISTENT 0x474f4f00

static u64 deny_bits = 0;
@@ -395,31 +394,22 @@ static void guest_ud_handler(struct ex_regs *regs)
regs->rip += KVM_FEP_LENGTH;
}

-static void run_guest(struct kvm_vm *vm)
+static void check_for_guest_assert(struct kvm_vcpu *vcpu)
{
- int rc;
-
- rc = _vcpu_run(vm, VCPU_ID);
- TEST_ASSERT(rc == 0, "vcpu_run failed: %d\n", rc);
-}
-
-static void check_for_guest_assert(struct kvm_vm *vm)
-{
- struct kvm_run *run = vcpu_state(vm, VCPU_ID);
struct ucall uc;

- if (run->exit_reason == KVM_EXIT_IO &&
- get_ucall(vm, VCPU_ID, &uc) == UCALL_ABORT) {
- TEST_FAIL("%s at %s:%ld", (const char *)uc.args[0],
- __FILE__, uc.args[1]);
+ if (vcpu->run->exit_reason == KVM_EXIT_IO &&
+ get_ucall(vcpu->vm, vcpu->id, &uc) == UCALL_ABORT) {
+ TEST_FAIL("%s at %s:%ld",
+ (const char *)uc.args[0], __FILE__, uc.args[1]);
}
}

-static void process_rdmsr(struct kvm_vm *vm, uint32_t msr_index)
+static void process_rdmsr(struct kvm_vcpu *vcpu, uint32_t msr_index)
{
- struct kvm_run *run = vcpu_state(vm, VCPU_ID);
+ struct kvm_run *run = vcpu->run;

- check_for_guest_assert(vm);
+ check_for_guest_assert(vcpu);

TEST_ASSERT(run->exit_reason == KVM_EXIT_X86_RDMSR,
"Unexpected exit reason: %u (%s),\n",
@@ -450,11 +440,11 @@ static void process_rdmsr(struct kvm_vm *vm, uint32_t msr_index)
}
}

-static void process_wrmsr(struct kvm_vm *vm, uint32_t msr_index)
+static void process_wrmsr(struct kvm_vcpu *vcpu, uint32_t msr_index)
{
- struct kvm_run *run = vcpu_state(vm, VCPU_ID);
+ struct kvm_run *run = vcpu->run;

- check_for_guest_assert(vm);
+ check_for_guest_assert(vcpu);

TEST_ASSERT(run->exit_reason == KVM_EXIT_X86_WRMSR,
"Unexpected exit reason: %u (%s),\n",
@@ -481,43 +471,43 @@ static void process_wrmsr(struct kvm_vm *vm, uint32_t msr_index)
}
}

-static void process_ucall_done(struct kvm_vm *vm)
+static void process_ucall_done(struct kvm_vcpu *vcpu)
{
- struct kvm_run *run = vcpu_state(vm, VCPU_ID);
+ struct kvm_run *run = vcpu->run;
struct ucall uc;

- check_for_guest_assert(vm);
+ check_for_guest_assert(vcpu);

TEST_ASSERT(run->exit_reason == KVM_EXIT_IO,
"Unexpected exit reason: %u (%s)",
run->exit_reason,
exit_reason_str(run->exit_reason));

- TEST_ASSERT(get_ucall(vm, VCPU_ID, &uc) == UCALL_DONE,
+ TEST_ASSERT(get_ucall(vcpu->vm, vcpu->id, &uc) == UCALL_DONE,
"Unexpected ucall command: %lu, expected UCALL_DONE (%d)",
uc.cmd, UCALL_DONE);
}

-static uint64_t process_ucall(struct kvm_vm *vm)
+static uint64_t process_ucall(struct kvm_vcpu *vcpu)
{
- struct kvm_run *run = vcpu_state(vm, VCPU_ID);
+ struct kvm_run *run = vcpu->run;
struct ucall uc = {};

- check_for_guest_assert(vm);
+ check_for_guest_assert(vcpu);

TEST_ASSERT(run->exit_reason == KVM_EXIT_IO,
"Unexpected exit reason: %u (%s)",
run->exit_reason,
exit_reason_str(run->exit_reason));

- switch (get_ucall(vm, VCPU_ID, &uc)) {
+ switch (get_ucall(vcpu->vm, vcpu->id, &uc)) {
case UCALL_SYNC:
break;
case UCALL_ABORT:
- check_for_guest_assert(vm);
+ check_for_guest_assert(vcpu);
break;
case UCALL_DONE:
- process_ucall_done(vm);
+ process_ucall_done(vcpu);
break;
default:
TEST_ASSERT(false, "Unexpected ucall");
@@ -526,41 +516,43 @@ static uint64_t process_ucall(struct kvm_vm *vm)
return uc.cmd;
}

-static void run_guest_then_process_rdmsr(struct kvm_vm *vm, uint32_t msr_index)
+static void run_guest_then_process_rdmsr(struct kvm_vcpu *vcpu,
+ uint32_t msr_index)
{
- run_guest(vm);
- process_rdmsr(vm, msr_index);
+ vcpu_run(vcpu->vm, vcpu->id);
+ process_rdmsr(vcpu, msr_index);
}

-static void run_guest_then_process_wrmsr(struct kvm_vm *vm, uint32_t msr_index)
+static void run_guest_then_process_wrmsr(struct kvm_vcpu *vcpu,
+ uint32_t msr_index)
{
- run_guest(vm);
- process_wrmsr(vm, msr_index);
+ vcpu_run(vcpu->vm, vcpu->id);
+ process_wrmsr(vcpu, msr_index);
}

-static uint64_t run_guest_then_process_ucall(struct kvm_vm *vm)
+static uint64_t run_guest_then_process_ucall(struct kvm_vcpu *vcpu)
{
- run_guest(vm);
- return process_ucall(vm);
+ vcpu_run(vcpu->vm, vcpu->id);
+ return process_ucall(vcpu);
}

-static void run_guest_then_process_ucall_done(struct kvm_vm *vm)
+static void run_guest_then_process_ucall_done(struct kvm_vcpu *vcpu)
{
- run_guest(vm);
- process_ucall_done(vm);
+ vcpu_run(vcpu->vm, vcpu->id);
+ process_ucall_done(vcpu);
}

-static void test_msr_filter_allow(void) {
+static void test_msr_filter_allow(void)
+{
struct kvm_enable_cap cap = {
.cap = KVM_CAP_X86_USER_SPACE_MSR,
.args[0] = KVM_MSR_EXIT_REASON_FILTER,
};
+ struct kvm_vcpu *vcpu;
struct kvm_vm *vm;
int rc;

- /* Create VM */
- vm = vm_create_default(VCPU_ID, 0, guest_code_filter_allow);
- vcpu_set_cpuid(vm, VCPU_ID, kvm_get_supported_cpuid());
+ vm = vm_create_with_one_vcpu(&vcpu, guest_code_filter_allow);

rc = kvm_check_cap(KVM_CAP_X86_USER_SPACE_MSR);
TEST_ASSERT(rc, "KVM_CAP_X86_USER_SPACE_MSR is available");
@@ -572,43 +564,43 @@ static void test_msr_filter_allow(void) {
vm_ioctl(vm, KVM_X86_SET_MSR_FILTER, &filter_allow);

vm_init_descriptor_tables(vm);
- vcpu_init_descriptor_tables(vm, VCPU_ID);
+ vcpu_init_descriptor_tables(vm, vcpu->id);

vm_install_exception_handler(vm, GP_VECTOR, guest_gp_handler);

/* Process guest code userspace exits. */
- run_guest_then_process_rdmsr(vm, MSR_IA32_XSS);
- run_guest_then_process_wrmsr(vm, MSR_IA32_XSS);
- run_guest_then_process_wrmsr(vm, MSR_IA32_XSS);
+ run_guest_then_process_rdmsr(vcpu, MSR_IA32_XSS);
+ run_guest_then_process_wrmsr(vcpu, MSR_IA32_XSS);
+ run_guest_then_process_wrmsr(vcpu, MSR_IA32_XSS);

- run_guest_then_process_rdmsr(vm, MSR_IA32_FLUSH_CMD);
- run_guest_then_process_wrmsr(vm, MSR_IA32_FLUSH_CMD);
- run_guest_then_process_wrmsr(vm, MSR_IA32_FLUSH_CMD);
+ run_guest_then_process_rdmsr(vcpu, MSR_IA32_FLUSH_CMD);
+ run_guest_then_process_wrmsr(vcpu, MSR_IA32_FLUSH_CMD);
+ run_guest_then_process_wrmsr(vcpu, MSR_IA32_FLUSH_CMD);

- run_guest_then_process_wrmsr(vm, MSR_NON_EXISTENT);
- run_guest_then_process_rdmsr(vm, MSR_NON_EXISTENT);
+ run_guest_then_process_wrmsr(vcpu, MSR_NON_EXISTENT);
+ run_guest_then_process_rdmsr(vcpu, MSR_NON_EXISTENT);

vm_install_exception_handler(vm, UD_VECTOR, guest_ud_handler);
- run_guest(vm);
+ vcpu_run(vm, vcpu->id);
vm_install_exception_handler(vm, UD_VECTOR, NULL);

- if (process_ucall(vm) != UCALL_DONE) {
+ if (process_ucall(vcpu) != UCALL_DONE) {
vm_install_exception_handler(vm, GP_VECTOR, guest_fep_gp_handler);

/* Process emulated rdmsr and wrmsr instructions. */
- run_guest_then_process_rdmsr(vm, MSR_IA32_XSS);
- run_guest_then_process_wrmsr(vm, MSR_IA32_XSS);
- run_guest_then_process_wrmsr(vm, MSR_IA32_XSS);
+ run_guest_then_process_rdmsr(vcpu, MSR_IA32_XSS);
+ run_guest_then_process_wrmsr(vcpu, MSR_IA32_XSS);
+ run_guest_then_process_wrmsr(vcpu, MSR_IA32_XSS);

- run_guest_then_process_rdmsr(vm, MSR_IA32_FLUSH_CMD);
- run_guest_then_process_wrmsr(vm, MSR_IA32_FLUSH_CMD);
- run_guest_then_process_wrmsr(vm, MSR_IA32_FLUSH_CMD);
+ run_guest_then_process_rdmsr(vcpu, MSR_IA32_FLUSH_CMD);
+ run_guest_then_process_wrmsr(vcpu, MSR_IA32_FLUSH_CMD);
+ run_guest_then_process_wrmsr(vcpu, MSR_IA32_FLUSH_CMD);

- run_guest_then_process_wrmsr(vm, MSR_NON_EXISTENT);
- run_guest_then_process_rdmsr(vm, MSR_NON_EXISTENT);
+ run_guest_then_process_wrmsr(vcpu, MSR_NON_EXISTENT);
+ run_guest_then_process_rdmsr(vcpu, MSR_NON_EXISTENT);

/* Confirm the guest completed without issues. */
- run_guest_then_process_ucall_done(vm);
+ run_guest_then_process_ucall_done(vcpu);
} else {
printf("To run the instruction emulated tests set the module parameter 'kvm.force_emulation_prefix=1'\n");
}
@@ -616,16 +608,16 @@ static void test_msr_filter_allow(void) {
kvm_vm_free(vm);
}

-static int handle_ucall(struct kvm_vm *vm)
+static int handle_ucall(struct kvm_vcpu *vcpu)
{
struct ucall uc;

- switch (get_ucall(vm, VCPU_ID, &uc)) {
+ switch (get_ucall(vcpu->vm, vcpu->id, &uc)) {
case UCALL_ABORT:
TEST_FAIL("Guest assertion not met");
break;
case UCALL_SYNC:
- vm_ioctl(vm, KVM_X86_SET_MSR_FILTER, &no_filter_deny);
+ vm_ioctl(vcpu->vm, KVM_X86_SET_MSR_FILTER, &no_filter_deny);
break;
case UCALL_DONE:
return 1;
@@ -673,21 +665,21 @@ static void handle_wrmsr(struct kvm_run *run)
}
}

-static void test_msr_filter_deny(void) {
+static void test_msr_filter_deny(void)
+{
struct kvm_enable_cap cap = {
.cap = KVM_CAP_X86_USER_SPACE_MSR,
.args[0] = KVM_MSR_EXIT_REASON_INVAL |
KVM_MSR_EXIT_REASON_UNKNOWN |
KVM_MSR_EXIT_REASON_FILTER,
};
+ struct kvm_vcpu *vcpu;
struct kvm_vm *vm;
struct kvm_run *run;
int rc;

- /* Create VM */
- vm = vm_create_default(VCPU_ID, 0, guest_code_filter_deny);
- vcpu_set_cpuid(vm, VCPU_ID, kvm_get_supported_cpuid());
- run = vcpu_state(vm, VCPU_ID);
+ vm = vm_create_with_one_vcpu(&vcpu, guest_code_filter_deny);
+ run = vcpu->run;

rc = kvm_check_cap(KVM_CAP_X86_USER_SPACE_MSR);
TEST_ASSERT(rc, "KVM_CAP_X86_USER_SPACE_MSR is available");
@@ -700,9 +692,7 @@ static void test_msr_filter_deny(void) {
vm_ioctl(vm, KVM_X86_SET_MSR_FILTER, &filter_deny);

while (1) {
- rc = _vcpu_run(vm, VCPU_ID);
-
- TEST_ASSERT(rc == 0, "vcpu_run failed: %d\n", rc);
+ vcpu_run(vm, vcpu->id);

switch (run->exit_reason) {
case KVM_EXIT_X86_RDMSR:
@@ -712,7 +702,7 @@ static void test_msr_filter_deny(void) {
handle_wrmsr(run);
break;
case KVM_EXIT_IO:
- if (handle_ucall(vm))
+ if (handle_ucall(vcpu))
goto done;
break;
}
@@ -726,17 +716,17 @@ static void test_msr_filter_deny(void) {
kvm_vm_free(vm);
}

-static void test_msr_permission_bitmap(void) {
+static void test_msr_permission_bitmap(void)
+{
struct kvm_enable_cap cap = {
.cap = KVM_CAP_X86_USER_SPACE_MSR,
.args[0] = KVM_MSR_EXIT_REASON_FILTER,
};
+ struct kvm_vcpu *vcpu;
struct kvm_vm *vm;
int rc;

- /* Create VM */
- vm = vm_create_default(VCPU_ID, 0, guest_code_permission_bitmap);
- vcpu_set_cpuid(vm, VCPU_ID, kvm_get_supported_cpuid());
+ vm = vm_create_with_one_vcpu(&vcpu, guest_code_permission_bitmap);

rc = kvm_check_cap(KVM_CAP_X86_USER_SPACE_MSR);
TEST_ASSERT(rc, "KVM_CAP_X86_USER_SPACE_MSR is available");
@@ -746,11 +736,12 @@ static void test_msr_permission_bitmap(void) {
TEST_ASSERT(rc, "KVM_CAP_X86_MSR_FILTER is available");

vm_ioctl(vm, KVM_X86_SET_MSR_FILTER, &filter_fs);
- run_guest_then_process_rdmsr(vm, MSR_FS_BASE);
- TEST_ASSERT(run_guest_then_process_ucall(vm) == UCALL_SYNC, "Expected ucall state to be UCALL_SYNC.");
+ run_guest_then_process_rdmsr(vcpu, MSR_FS_BASE);
+ TEST_ASSERT(run_guest_then_process_ucall(vcpu) == UCALL_SYNC,
+ "Expected ucall state to be UCALL_SYNC.");
vm_ioctl(vm, KVM_X86_SET_MSR_FILTER, &filter_gs);
- run_guest_then_process_rdmsr(vm, MSR_GS_BASE);
- run_guest_then_process_ucall_done(vm);
+ run_guest_then_process_rdmsr(vcpu, MSR_GS_BASE);
+ run_guest_then_process_ucall_done(vcpu);

kvm_vm_free(vm);
}
--
2.36.0.464.gb9c8b46e94-goog