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Diffstat (limited to 'arch/x86/kvm/x86.c')
-rw-r--r--arch/x86/kvm/x86.c99
1 files changed, 69 insertions, 30 deletions
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index ff395f812719..5d530521f11d 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -213,6 +213,7 @@ struct kvm_stats_debugfs_item debugfs_entries[] = {
{ "mmu_unsync", VM_STAT(mmu_unsync) },
{ "remote_tlb_flush", VM_STAT(remote_tlb_flush) },
{ "largepages", VM_STAT(lpages, .mode = 0444) },
+ { "nx_largepages_splitted", VM_STAT(nx_lpage_splits, .mode = 0444) },
{ "max_mmu_page_hash_collisions",
VM_STAT(max_mmu_page_hash_collisions) },
{ NULL }
@@ -1132,13 +1133,15 @@ EXPORT_SYMBOL_GPL(kvm_rdpmc);
* List of msr numbers which we expose to userspace through KVM_GET_MSRS
* and KVM_SET_MSRS, and KVM_GET_MSR_INDEX_LIST.
*
- * This list is modified at module load time to reflect the
+ * The three MSR lists(msrs_to_save, emulated_msrs, msr_based_features)
+ * extract the supported MSRs from the related const lists.
+ * msrs_to_save is selected from the msrs_to_save_all to reflect the
* capabilities of the host cpu. This capabilities test skips MSRs that are
- * kvm-specific. Those are put in emulated_msrs; filtering of emulated_msrs
+ * kvm-specific. Those are put in emulated_msrs_all; filtering of emulated_msrs
* may depend on host virtualization features rather than host cpu features.
*/
-static u32 msrs_to_save[] = {
+static const u32 msrs_to_save_all[] = {
MSR_IA32_SYSENTER_CS, MSR_IA32_SYSENTER_ESP, MSR_IA32_SYSENTER_EIP,
MSR_STAR,
#ifdef CONFIG_X86_64
@@ -1179,9 +1182,10 @@ static u32 msrs_to_save[] = {
MSR_ARCH_PERFMON_EVENTSEL0 + 16, MSR_ARCH_PERFMON_EVENTSEL0 + 17,
};
+static u32 msrs_to_save[ARRAY_SIZE(msrs_to_save_all)];
static unsigned num_msrs_to_save;
-static u32 emulated_msrs[] = {
+static const u32 emulated_msrs_all[] = {
MSR_KVM_SYSTEM_TIME, MSR_KVM_WALL_CLOCK,
MSR_KVM_SYSTEM_TIME_NEW, MSR_KVM_WALL_CLOCK_NEW,
HV_X64_MSR_GUEST_OS_ID, HV_X64_MSR_HYPERCALL,
@@ -1220,7 +1224,7 @@ static u32 emulated_msrs[] = {
* by arch/x86/kvm/vmx/nested.c based on CPUID or other MSRs.
* We always support the "true" VMX control MSRs, even if the host
* processor does not, so I am putting these registers here rather
- * than in msrs_to_save.
+ * than in msrs_to_save_all.
*/
MSR_IA32_VMX_BASIC,
MSR_IA32_VMX_TRUE_PINBASED_CTLS,
@@ -1239,13 +1243,14 @@ static u32 emulated_msrs[] = {
MSR_KVM_POLL_CONTROL,
};
+static u32 emulated_msrs[ARRAY_SIZE(emulated_msrs_all)];
static unsigned num_emulated_msrs;
/*
* List of msr numbers which are used to expose MSR-based features that
* can be used by a hypervisor to validate requested CPU features.
*/
-static u32 msr_based_features[] = {
+static const u32 msr_based_features_all[] = {
MSR_IA32_VMX_BASIC,
MSR_IA32_VMX_TRUE_PINBASED_CTLS,
MSR_IA32_VMX_PINBASED_CTLS,
@@ -1270,6 +1275,7 @@ static u32 msr_based_features[] = {
MSR_IA32_ARCH_CAPABILITIES,
};
+static u32 msr_based_features[ARRAY_SIZE(msr_based_features_all)];
static unsigned int num_msr_based_features;
static u64 kvm_get_arch_capabilities(void)
@@ -1280,6 +1286,14 @@ static u64 kvm_get_arch_capabilities(void)
rdmsrl(MSR_IA32_ARCH_CAPABILITIES, data);
/*
+ * If nx_huge_pages is enabled, KVM's shadow paging will ensure that
+ * the nested hypervisor runs with NX huge pages. If it is not,
+ * L1 is anyway vulnerable to ITLB_MULTIHIT explots from other
+ * L1 guests, so it need not worry about its own (L2) guests.
+ */
+ data |= ARCH_CAP_PSCHANGE_MC_NO;
+
+ /*
* If we're doing cache flushes (either "always" or "cond")
* we will do one whenever the guest does a vmlaunch/vmresume.
* If an outer hypervisor is doing the cache flush for us
@@ -1298,6 +1312,25 @@ static u64 kvm_get_arch_capabilities(void)
if (!boot_cpu_has_bug(X86_BUG_MDS))
data |= ARCH_CAP_MDS_NO;
+ /*
+ * On TAA affected systems, export MDS_NO=0 when:
+ * - TSX is enabled on the host, i.e. X86_FEATURE_RTM=1.
+ * - Updated microcode is present. This is detected by
+ * the presence of ARCH_CAP_TSX_CTRL_MSR and ensures
+ * that VERW clears CPU buffers.
+ *
+ * When MDS_NO=0 is exported, guests deploy clear CPU buffer
+ * mitigation and don't complain:
+ *
+ * "Vulnerable: Clear CPU buffers attempted, no microcode"
+ *
+ * If TSX is disabled on the system, guests are also mitigated against
+ * TAA and clear CPU buffer mitigation is not required for guests.
+ */
+ if (boot_cpu_has_bug(X86_BUG_TAA) && boot_cpu_has(X86_FEATURE_RTM) &&
+ (data & ARCH_CAP_TSX_CTRL_MSR))
+ data &= ~ARCH_CAP_MDS_NO;
+
return data;
}
@@ -5090,22 +5123,26 @@ static void kvm_init_msr_list(void)
{
struct x86_pmu_capability x86_pmu;
u32 dummy[2];
- unsigned i, j;
+ unsigned i;
BUILD_BUG_ON_MSG(INTEL_PMC_MAX_FIXED != 4,
- "Please update the fixed PMCs in msrs_to_save[]");
+ "Please update the fixed PMCs in msrs_to_saved_all[]");
perf_get_x86_pmu_capability(&x86_pmu);
- for (i = j = 0; i < ARRAY_SIZE(msrs_to_save); i++) {
- if (rdmsr_safe(msrs_to_save[i], &dummy[0], &dummy[1]) < 0)
+ num_msrs_to_save = 0;
+ num_emulated_msrs = 0;
+ num_msr_based_features = 0;
+
+ for (i = 0; i < ARRAY_SIZE(msrs_to_save_all); i++) {
+ if (rdmsr_safe(msrs_to_save_all[i], &dummy[0], &dummy[1]) < 0)
continue;
/*
* Even MSRs that are valid in the host may not be exposed
* to the guests in some cases.
*/
- switch (msrs_to_save[i]) {
+ switch (msrs_to_save_all[i]) {
case MSR_IA32_BNDCFGS:
if (!kvm_mpx_supported())
continue;
@@ -5133,17 +5170,17 @@ static void kvm_init_msr_list(void)
break;
case MSR_IA32_RTIT_ADDR0_A ... MSR_IA32_RTIT_ADDR3_B: {
if (!kvm_x86_ops->pt_supported() ||
- msrs_to_save[i] - MSR_IA32_RTIT_ADDR0_A >=
+ msrs_to_save_all[i] - MSR_IA32_RTIT_ADDR0_A >=
intel_pt_validate_hw_cap(PT_CAP_num_address_ranges) * 2)
continue;
break;
case MSR_ARCH_PERFMON_PERFCTR0 ... MSR_ARCH_PERFMON_PERFCTR0 + 17:
- if (msrs_to_save[i] - MSR_ARCH_PERFMON_PERFCTR0 >=
+ if (msrs_to_save_all[i] - MSR_ARCH_PERFMON_PERFCTR0 >=
min(INTEL_PMC_MAX_GENERIC, x86_pmu.num_counters_gp))
continue;
break;
case MSR_ARCH_PERFMON_EVENTSEL0 ... MSR_ARCH_PERFMON_EVENTSEL0 + 17:
- if (msrs_to_save[i] - MSR_ARCH_PERFMON_EVENTSEL0 >=
+ if (msrs_to_save_all[i] - MSR_ARCH_PERFMON_EVENTSEL0 >=
min(INTEL_PMC_MAX_GENERIC, x86_pmu.num_counters_gp))
continue;
}
@@ -5151,34 +5188,25 @@ static void kvm_init_msr_list(void)
break;
}
- if (j < i)
- msrs_to_save[j] = msrs_to_save[i];
- j++;
+ msrs_to_save[num_msrs_to_save++] = msrs_to_save_all[i];
}
- num_msrs_to_save = j;
- for (i = j = 0; i < ARRAY_SIZE(emulated_msrs); i++) {
- if (!kvm_x86_ops->has_emulated_msr(emulated_msrs[i]))
+ for (i = 0; i < ARRAY_SIZE(emulated_msrs_all); i++) {
+ if (!kvm_x86_ops->has_emulated_msr(emulated_msrs_all[i]))
continue;
- if (j < i)
- emulated_msrs[j] = emulated_msrs[i];
- j++;
+ emulated_msrs[num_emulated_msrs++] = emulated_msrs_all[i];
}
- num_emulated_msrs = j;
- for (i = j = 0; i < ARRAY_SIZE(msr_based_features); i++) {
+ for (i = 0; i < ARRAY_SIZE(msr_based_features_all); i++) {
struct kvm_msr_entry msr;
- msr.index = msr_based_features[i];
+ msr.index = msr_based_features_all[i];
if (kvm_get_msr_feature(&msr))
continue;
- if (j < i)
- msr_based_features[j] = msr_based_features[i];
- j++;
+ msr_based_features[num_msr_based_features++] = msr_based_features_all[i];
}
- num_msr_based_features = j;
}
static int vcpu_mmio_write(struct kvm_vcpu *vcpu, gpa_t addr, int len,
@@ -9428,6 +9456,7 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
INIT_HLIST_HEAD(&kvm->arch.mask_notifier_list);
INIT_LIST_HEAD(&kvm->arch.active_mmu_pages);
INIT_LIST_HEAD(&kvm->arch.zapped_obsolete_pages);
+ INIT_LIST_HEAD(&kvm->arch.lpage_disallowed_mmu_pages);
INIT_LIST_HEAD(&kvm->arch.assigned_dev_head);
atomic_set(&kvm->arch.noncoherent_dma_count, 0);
@@ -9456,6 +9485,11 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
return kvm_x86_ops->vm_init(kvm);
}
+int kvm_arch_post_init_vm(struct kvm *kvm)
+{
+ return kvm_mmu_post_init_vm(kvm);
+}
+
static void kvm_unload_vcpu_mmu(struct kvm_vcpu *vcpu)
{
vcpu_load(vcpu);
@@ -9557,6 +9591,11 @@ int x86_set_memory_region(struct kvm *kvm, int id, gpa_t gpa, u32 size)
}
EXPORT_SYMBOL_GPL(x86_set_memory_region);
+void kvm_arch_pre_destroy_vm(struct kvm *kvm)
+{
+ kvm_mmu_pre_destroy_vm(kvm);
+}
+
void kvm_arch_destroy_vm(struct kvm *kvm)
{
if (current->mm == kvm->mm) {
generated by cgit v1.2.3 (git 2.25.1) at 2024-04-25 20:40:05 +0000