[PATCH 3/3] selftests: kvm: check dynamic bits against KVM_X86_XCOMP_GUEST_SUPP

From: Paolo Bonzini
Date: Wed Jan 26 2022 - 10:22:29 EST


Provide coverage for the new API.

Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
---
tools/arch/x86/include/uapi/asm/kvm.h | 3 +++
tools/include/uapi/linux/kvm.h | 1 +
.../testing/selftests/kvm/lib/x86_64/processor.c | 15 +++++++++++++++
3 files changed, 19 insertions(+)

diff --git a/tools/arch/x86/include/uapi/asm/kvm.h b/tools/arch/x86/include/uapi/asm/kvm.h
index 2da3316bb559..bf6e96011dfe 100644
--- a/tools/arch/x86/include/uapi/asm/kvm.h
+++ b/tools/arch/x86/include/uapi/asm/kvm.h
@@ -452,6 +452,9 @@ struct kvm_sync_regs {

#define KVM_STATE_VMX_PREEMPTION_TIMER_DEADLINE 0x00000001

+/* attributes for system fd (group 0) */
+#define KVM_X86_XCOMP_GUEST_SUPP 0
+
struct kvm_vmx_nested_state_data {
__u8 vmcs12[KVM_STATE_NESTED_VMX_VMCS_SIZE];
__u8 shadow_vmcs12[KVM_STATE_NESTED_VMX_VMCS_SIZE];
diff --git a/tools/include/uapi/linux/kvm.h b/tools/include/uapi/linux/kvm.h
index 9563d294f181..b46bcdb0cab1 100644
--- a/tools/include/uapi/linux/kvm.h
+++ b/tools/include/uapi/linux/kvm.h
@@ -1133,6 +1133,7 @@ struct kvm_ppc_resize_hpt {
#define KVM_CAP_VM_MOVE_ENC_CONTEXT_FROM 206
#define KVM_CAP_VM_GPA_BITS 207
#define KVM_CAP_XSAVE2 208
+#define KVM_CAP_SYS_ATTRIBUTES 209

#ifdef KVM_CAP_IRQ_ROUTING

diff --git a/tools/testing/selftests/kvm/lib/x86_64/processor.c b/tools/testing/selftests/kvm/lib/x86_64/processor.c
index c1d1c195a838..9f000dfb5594 100644
--- a/tools/testing/selftests/kvm/lib/x86_64/processor.c
+++ b/tools/testing/selftests/kvm/lib/x86_64/processor.c
@@ -667,8 +667,23 @@ static bool is_xfd_supported(void)

void vm_xsave_req_perm(int bit)
{
+ int kvm_fd;
u64 bitmask;
long rc;
+ struct kvm_device_attr attr = {
+ .group = 0,
+ .attr = KVM_X86_XCOMP_GUEST_SUPP,
+ .addr = (unsigned long) &bitmask
+ };
+
+ kvm_fd = open_kvm_dev_path_or_exit();
+ rc = ioctl(kvm_fd, KVM_GET_DEVICE_ATTR, &attr);
+ close(kvm_fd);
+ if (rc == -1 && (errno == ENXIO || errno == EINVAL))
+ exit(KSFT_SKIP);
+ TEST_ASSERT(rc == 0, "KVM_GET_DEVICE_ATTR(0, KVM_X86_XCOMP_GUEST_SUPP) error: %ld", rc);
+ if (!(bitmask & (1ULL << bit)))
+ exit(KSFT_SKIP);

if (!is_xfd_supported())
exit(KSFT_SKIP);
--
2.31.1