kvm/x86_64/vmx_msrs_test.c

0001 // SPDX-License-Identifier: GPL-2.0-only
0002 /*
0003  * VMX control MSR test
0004  *
0005  * Copyright (C) 2022 Google LLC.
0006  *
0007  * Tests for KVM ownership of bits in the VMX entry/exit control MSRs. Checks
0008  * that KVM will set owned bits where appropriate, and will not if
0009  * KVM_X86_QUIRK_TWEAK_VMX_CTRL_MSRS is disabled.
0010  */
0011 #include <linux/bitmap.h>
0012 #include "kvm_util.h"
0013 #include "vmx.h"
0014
0015 static void vmx_fixed1_msr_test(struct kvm_vcpu *vcpu, uint32_t msr_index,
0016                   uint64_t mask)
0017 {
0018     uint64_t val = vcpu_get_msr(vcpu, msr_index);
0019     uint64_t bit;
0020
0021     mask &= val;
0022
0023     for_each_set_bit(bit, &mask, 64) {
0024         vcpu_set_msr(vcpu, msr_index, val & ~BIT_ULL(bit));
0025         vcpu_set_msr(vcpu, msr_index, val);
0026     }
0027 }
0028
0029 static void vmx_fixed0_msr_test(struct kvm_vcpu *vcpu, uint32_t msr_index,
0030                 uint64_t mask)
0031 {
0032     uint64_t val = vcpu_get_msr(vcpu, msr_index);
0033     uint64_t bit;
0034
0035     mask = ~mask | val;
0036
0037     for_each_clear_bit(bit, &mask, 64) {
0038         vcpu_set_msr(vcpu, msr_index, val | BIT_ULL(bit));
0039         vcpu_set_msr(vcpu, msr_index, val);
0040     }
0041 }
0042
0043 static void vmx_fixed0and1_msr_test(struct kvm_vcpu *vcpu, uint32_t msr_index)
0044 {
0045     vmx_fixed0_msr_test(vcpu, msr_index, GENMASK_ULL(31, 0));
0046     vmx_fixed1_msr_test(vcpu, msr_index, GENMASK_ULL(63, 32));
0047 }
0048
0049 static void vmx_save_restore_msrs_test(struct kvm_vcpu *vcpu)
0050 {
0051     vcpu_set_msr(vcpu, MSR_IA32_VMX_VMCS_ENUM, 0);
0052     vcpu_set_msr(vcpu, MSR_IA32_VMX_VMCS_ENUM, -1ull);
0053
0054     vmx_fixed1_msr_test(vcpu, MSR_IA32_VMX_BASIC,
0055                 BIT_ULL(49) | BIT_ULL(54) | BIT_ULL(55));
0056
0057     vmx_fixed1_msr_test(vcpu, MSR_IA32_VMX_MISC,
0058                 BIT_ULL(5) | GENMASK_ULL(8, 6) | BIT_ULL(14) |
0059                 BIT_ULL(15) | BIT_ULL(28) | BIT_ULL(29) | BIT_ULL(30));
0060
0061     vmx_fixed0and1_msr_test(vcpu, MSR_IA32_VMX_PROCBASED_CTLS2);
0062     vmx_fixed1_msr_test(vcpu, MSR_IA32_VMX_EPT_VPID_CAP, -1ull);
0063     vmx_fixed0and1_msr_test(vcpu, MSR_IA32_VMX_TRUE_PINBASED_CTLS);
0064     vmx_fixed0and1_msr_test(vcpu, MSR_IA32_VMX_TRUE_PROCBASED_CTLS);
0065     vmx_fixed0and1_msr_test(vcpu, MSR_IA32_VMX_TRUE_EXIT_CTLS);
0066     vmx_fixed0and1_msr_test(vcpu, MSR_IA32_VMX_TRUE_ENTRY_CTLS);
0067     vmx_fixed1_msr_test(vcpu, MSR_IA32_VMX_VMFUNC, -1ull);
0068 }
0069
0070 int main(void)
0071 {
0072     struct kvm_vcpu *vcpu;
0073     struct kvm_vm *vm;
0074
0075     TEST_REQUIRE(kvm_has_cap(KVM_CAP_DISABLE_QUIRKS2));
0076     TEST_REQUIRE(kvm_cpu_has(X86_FEATURE_VMX));
0077
0078     /* No need to actually do KVM_RUN, thus no guest code. */
0079     vm = vm_create_with_one_vcpu(&vcpu, NULL);
0080
0081     vmx_save_restore_msrs_test(vcpu);
0082
0083     kvm_vm_free(vm);
0084 }