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-rw-r--r--arch/x86/kvm/cpuid.c23
-rw-r--r--arch/x86/kvm/cpuid.h1
-rw-r--r--arch/x86/kvm/mmu/mmu.c22
-rw-r--r--arch/x86/kvm/mmu/spte.c16
-rw-r--r--arch/x86/kvm/mmu/spte.h16
-rw-r--r--arch/x86/kvm/vmx/evmcs.c3
-rw-r--r--arch/x86/kvm/vmx/evmcs.h3
-rw-r--r--arch/x86/kvm/vmx/vmx.c6
-rw-r--r--arch/x86/kvm/x86.c80
-rw-r--r--arch/x86/kvm/x86.h8
10 files changed, 116 insertions, 62 deletions
diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index 06a278b3701d..d50041f570e8 100644
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -90,6 +90,20 @@ static int kvm_check_cpuid(struct kvm_cpuid_entry2 *entries, int nent)
return 0;
}
+void kvm_update_pv_runtime(struct kvm_vcpu *vcpu)
+{
+ struct kvm_cpuid_entry2 *best;
+
+ best = kvm_find_cpuid_entry(vcpu, KVM_CPUID_FEATURES, 0);
+
+ /*
+ * save the feature bitmap to avoid cpuid lookup for every PV
+ * operation
+ */
+ if (best)
+ vcpu->arch.pv_cpuid.features = best->eax;
+}
+
void kvm_update_cpuid_runtime(struct kvm_vcpu *vcpu)
{
struct kvm_cpuid_entry2 *best;
@@ -124,13 +138,6 @@ void kvm_update_cpuid_runtime(struct kvm_vcpu *vcpu)
(best->eax & (1 << KVM_FEATURE_PV_UNHALT)))
best->eax &= ~(1 << KVM_FEATURE_PV_UNHALT);
- /*
- * save the feature bitmap to avoid cpuid lookup for every PV
- * operation
- */
- if (best)
- vcpu->arch.pv_cpuid.features = best->eax;
-
if (!kvm_check_has_quirk(vcpu->kvm, KVM_X86_QUIRK_MISC_ENABLE_NO_MWAIT)) {
best = kvm_find_cpuid_entry(vcpu, 0x1, 0);
if (best)
@@ -162,6 +169,8 @@ static void kvm_vcpu_after_set_cpuid(struct kvm_vcpu *vcpu)
vcpu->arch.guest_supported_xcr0 =
(best->eax | ((u64)best->edx << 32)) & supported_xcr0;
+ kvm_update_pv_runtime(vcpu);
+
vcpu->arch.maxphyaddr = cpuid_query_maxphyaddr(vcpu);
kvm_mmu_reset_context(vcpu);
diff --git a/arch/x86/kvm/cpuid.h b/arch/x86/kvm/cpuid.h
index bf8577947ed2..f7a6e8f83783 100644
--- a/arch/x86/kvm/cpuid.h
+++ b/arch/x86/kvm/cpuid.h
@@ -11,6 +11,7 @@ extern u32 kvm_cpu_caps[NCAPINTS] __read_mostly;
void kvm_set_cpu_caps(void);
void kvm_update_cpuid_runtime(struct kvm_vcpu *vcpu);
+void kvm_update_pv_runtime(struct kvm_vcpu *vcpu);
struct kvm_cpuid_entry2 *kvm_find_cpuid_entry(struct kvm_vcpu *vcpu,
u32 function, u32 index);
int kvm_dev_ioctl_get_cpuid(struct kvm_cpuid2 *cpuid,
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 17587f496ec7..5bb1939b65d8 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -225,7 +225,7 @@ static gfn_t get_mmio_spte_gfn(u64 spte)
{
u64 gpa = spte & shadow_nonpresent_or_rsvd_lower_gfn_mask;
- gpa |= (spte >> shadow_nonpresent_or_rsvd_mask_len)
+ gpa |= (spte >> SHADOW_NONPRESENT_OR_RSVD_MASK_LEN)
& shadow_nonpresent_or_rsvd_mask;
return gpa >> PAGE_SHIFT;
@@ -591,15 +591,15 @@ static u64 mmu_spte_get_lockless(u64 *sptep)
static u64 restore_acc_track_spte(u64 spte)
{
u64 new_spte = spte;
- u64 saved_bits = (spte >> shadow_acc_track_saved_bits_shift)
- & shadow_acc_track_saved_bits_mask;
+ u64 saved_bits = (spte >> SHADOW_ACC_TRACK_SAVED_BITS_SHIFT)
+ & SHADOW_ACC_TRACK_SAVED_BITS_MASK;
WARN_ON_ONCE(spte_ad_enabled(spte));
WARN_ON_ONCE(!is_access_track_spte(spte));
new_spte &= ~shadow_acc_track_mask;
- new_spte &= ~(shadow_acc_track_saved_bits_mask <<
- shadow_acc_track_saved_bits_shift);
+ new_spte &= ~(SHADOW_ACC_TRACK_SAVED_BITS_MASK <<
+ SHADOW_ACC_TRACK_SAVED_BITS_SHIFT);
new_spte |= saved_bits;
return new_spte;
@@ -856,12 +856,14 @@ static int pte_list_add(struct kvm_vcpu *vcpu, u64 *spte,
} else {
rmap_printk("pte_list_add: %p %llx many->many\n", spte, *spte);
desc = (struct pte_list_desc *)(rmap_head->val & ~1ul);
- while (desc->sptes[PTE_LIST_EXT-1] && desc->more) {
- desc = desc->more;
+ while (desc->sptes[PTE_LIST_EXT-1]) {
count += PTE_LIST_EXT;
- }
- if (desc->sptes[PTE_LIST_EXT-1]) {
- desc->more = mmu_alloc_pte_list_desc(vcpu);
+
+ if (!desc->more) {
+ desc->more = mmu_alloc_pte_list_desc(vcpu);
+ desc = desc->more;
+ break;
+ }
desc = desc->more;
}
for (i = 0; desc->sptes[i]; ++i)
diff --git a/arch/x86/kvm/mmu/spte.c b/arch/x86/kvm/mmu/spte.c
index d9c5665a55e9..fcac2cac78fe 100644
--- a/arch/x86/kvm/mmu/spte.c
+++ b/arch/x86/kvm/mmu/spte.c
@@ -55,7 +55,7 @@ u64 make_mmio_spte(struct kvm_vcpu *vcpu, u64 gfn, unsigned int access)
mask |= shadow_mmio_value | access;
mask |= gpa | shadow_nonpresent_or_rsvd_mask;
mask |= (gpa & shadow_nonpresent_or_rsvd_mask)
- << shadow_nonpresent_or_rsvd_mask_len;
+ << SHADOW_NONPRESENT_OR_RSVD_MASK_LEN;
return mask;
}
@@ -231,12 +231,12 @@ u64 mark_spte_for_access_track(u64 spte)
!spte_can_locklessly_be_made_writable(spte),
"kvm: Writable SPTE is not locklessly dirty-trackable\n");
- WARN_ONCE(spte & (shadow_acc_track_saved_bits_mask <<
- shadow_acc_track_saved_bits_shift),
+ WARN_ONCE(spte & (SHADOW_ACC_TRACK_SAVED_BITS_MASK <<
+ SHADOW_ACC_TRACK_SAVED_BITS_SHIFT),
"kvm: Access Tracking saved bit locations are not zero\n");
- spte |= (spte & shadow_acc_track_saved_bits_mask) <<
- shadow_acc_track_saved_bits_shift;
+ spte |= (spte & SHADOW_ACC_TRACK_SAVED_BITS_MASK) <<
+ SHADOW_ACC_TRACK_SAVED_BITS_SHIFT;
spte &= ~shadow_acc_track_mask;
return spte;
@@ -245,7 +245,7 @@ u64 mark_spte_for_access_track(u64 spte)
void kvm_mmu_set_mmio_spte_mask(u64 mmio_value, u64 access_mask)
{
BUG_ON((u64)(unsigned)access_mask != access_mask);
- WARN_ON(mmio_value & (shadow_nonpresent_or_rsvd_mask << shadow_nonpresent_or_rsvd_mask_len));
+ WARN_ON(mmio_value & (shadow_nonpresent_or_rsvd_mask << SHADOW_NONPRESENT_OR_RSVD_MASK_LEN));
WARN_ON(mmio_value & shadow_nonpresent_or_rsvd_lower_gfn_mask);
shadow_mmio_value = mmio_value | SPTE_MMIO_MASK;
shadow_mmio_access_mask = access_mask;
@@ -306,9 +306,9 @@ void kvm_mmu_reset_all_pte_masks(void)
low_phys_bits = boot_cpu_data.x86_phys_bits;
if (boot_cpu_has_bug(X86_BUG_L1TF) &&
!WARN_ON_ONCE(boot_cpu_data.x86_cache_bits >=
- 52 - shadow_nonpresent_or_rsvd_mask_len)) {
+ 52 - SHADOW_NONPRESENT_OR_RSVD_MASK_LEN)) {
low_phys_bits = boot_cpu_data.x86_cache_bits
- - shadow_nonpresent_or_rsvd_mask_len;
+ - SHADOW_NONPRESENT_OR_RSVD_MASK_LEN;
shadow_nonpresent_or_rsvd_mask =
rsvd_bits(low_phys_bits, boot_cpu_data.x86_cache_bits - 1);
}
diff --git a/arch/x86/kvm/mmu/spte.h b/arch/x86/kvm/mmu/spte.h
index 4ecf40e0b8fe..5c75a451c000 100644
--- a/arch/x86/kvm/mmu/spte.h
+++ b/arch/x86/kvm/mmu/spte.h
@@ -105,19 +105,19 @@ extern u64 __read_mostly shadow_acc_track_mask;
extern u64 __read_mostly shadow_nonpresent_or_rsvd_mask;
/*
+ * The number of high-order 1 bits to use in the mask above.
+ */
+#define SHADOW_NONPRESENT_OR_RSVD_MASK_LEN 5
+
+/*
* The mask/shift to use for saving the original R/X bits when marking the PTE
* as not-present for access tracking purposes. We do not save the W bit as the
* PTEs being access tracked also need to be dirty tracked, so the W bit will be
* restored only when a write is attempted to the page.
*/
-static const u64 shadow_acc_track_saved_bits_mask = PT64_EPT_READABLE_MASK |
- PT64_EPT_EXECUTABLE_MASK;
-static const u64 shadow_acc_track_saved_bits_shift = PT64_SECOND_AVAIL_BITS_SHIFT;
-
-/*
- * The number of high-order 1 bits to use in the mask above.
- */
-static const u64 shadow_nonpresent_or_rsvd_mask_len = 5;
+#define SHADOW_ACC_TRACK_SAVED_BITS_MASK (PT64_EPT_READABLE_MASK | \
+ PT64_EPT_EXECUTABLE_MASK)
+#define SHADOW_ACC_TRACK_SAVED_BITS_SHIFT PT64_SECOND_AVAIL_BITS_SHIFT
/*
* In some cases, we need to preserve the GFN of a non-present or reserved
diff --git a/arch/x86/kvm/vmx/evmcs.c b/arch/x86/kvm/vmx/evmcs.c
index e5325bd0f304..f3199bb02f22 100644
--- a/arch/x86/kvm/vmx/evmcs.c
+++ b/arch/x86/kvm/vmx/evmcs.c
@@ -297,14 +297,13 @@ const struct evmcs_field vmcs_field_to_evmcs_1[] = {
};
const unsigned int nr_evmcs_1_fields = ARRAY_SIZE(vmcs_field_to_evmcs_1);
-void evmcs_sanitize_exec_ctrls(struct vmcs_config *vmcs_conf)
+__init void evmcs_sanitize_exec_ctrls(struct vmcs_config *vmcs_conf)
{
vmcs_conf->pin_based_exec_ctrl &= ~EVMCS1_UNSUPPORTED_PINCTRL;
vmcs_conf->cpu_based_2nd_exec_ctrl &= ~EVMCS1_UNSUPPORTED_2NDEXEC;
vmcs_conf->vmexit_ctrl &= ~EVMCS1_UNSUPPORTED_VMEXIT_CTRL;
vmcs_conf->vmentry_ctrl &= ~EVMCS1_UNSUPPORTED_VMENTRY_CTRL;
-
}
#endif
diff --git a/arch/x86/kvm/vmx/evmcs.h b/arch/x86/kvm/vmx/evmcs.h
index e5f7a7ebf27d..bd41d9462355 100644
--- a/arch/x86/kvm/vmx/evmcs.h
+++ b/arch/x86/kvm/vmx/evmcs.h
@@ -185,7 +185,7 @@ static inline void evmcs_load(u64 phys_addr)
vp_ap->enlighten_vmentry = 1;
}
-void evmcs_sanitize_exec_ctrls(struct vmcs_config *vmcs_conf);
+__init void evmcs_sanitize_exec_ctrls(struct vmcs_config *vmcs_conf);
#else /* !IS_ENABLED(CONFIG_HYPERV) */
static inline void evmcs_write64(unsigned long field, u64 value) {}
static inline void evmcs_write32(unsigned long field, u32 value) {}
@@ -194,7 +194,6 @@ static inline u64 evmcs_read64(unsigned long field) { return 0; }
static inline u32 evmcs_read32(unsigned long field) { return 0; }
static inline u16 evmcs_read16(unsigned long field) { return 0; }
static inline void evmcs_load(u64 phys_addr) {}
-static inline void evmcs_sanitize_exec_ctrls(struct vmcs_config *vmcs_conf) {}
static inline void evmcs_touch_msr_bitmap(void) {}
#endif /* IS_ENABLED(CONFIG_HYPERV) */
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index d14c94d0aff1..47b8357b9751 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -2560,8 +2560,10 @@ static __init int setup_vmcs_config(struct vmcs_config *vmcs_conf,
vmcs_conf->vmexit_ctrl = _vmexit_control;
vmcs_conf->vmentry_ctrl = _vmentry_control;
- if (static_branch_unlikely(&enable_evmcs))
+#if IS_ENABLED(CONFIG_HYPERV)
+ if (enlightened_vmcs)
evmcs_sanitize_exec_ctrls(vmcs_conf);
+#endif
return 0;
}
@@ -6834,7 +6836,6 @@ static void vmx_free_vcpu(struct kvm_vcpu *vcpu)
static int vmx_create_vcpu(struct kvm_vcpu *vcpu)
{
struct vcpu_vmx *vmx;
- unsigned long *msr_bitmap;
int i, cpu, err;
BUILD_BUG_ON(offsetof(struct vcpu_vmx, vcpu) != 0);
@@ -6894,7 +6895,6 @@ static int vmx_create_vcpu(struct kvm_vcpu *vcpu)
bitmap_fill(vmx->shadow_msr_intercept.read, MAX_POSSIBLE_PASSTHROUGH_MSRS);
bitmap_fill(vmx->shadow_msr_intercept.write, MAX_POSSIBLE_PASSTHROUGH_MSRS);
- msr_bitmap = vmx->vmcs01.msr_bitmap;
vmx_disable_intercept_for_msr(vcpu, MSR_IA32_TSC, MSR_TYPE_R);
vmx_disable_intercept_for_msr(vcpu, MSR_FS_BASE, MSR_TYPE_RW);
vmx_disable_intercept_for_msr(vcpu, MSR_GS_BASE, MSR_TYPE_RW);
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 397f599b20e5..447edc0d1d5a 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -255,24 +255,23 @@ static struct kmem_cache *x86_emulator_cache;
/*
* When called, it means the previous get/set msr reached an invalid msr.
- * Return 0 if we want to ignore/silent this failed msr access, or 1 if we want
- * to fail the caller.
+ * Return true if we want to ignore/silent this failed msr access.
*/
-static int kvm_msr_ignored_check(struct kvm_vcpu *vcpu, u32 msr,
- u64 data, bool write)
+static bool kvm_msr_ignored_check(struct kvm_vcpu *vcpu, u32 msr,
+ u64 data, bool write)
{
const char *op = write ? "wrmsr" : "rdmsr";
if (ignore_msrs) {
if (report_ignored_msrs)
- vcpu_unimpl(vcpu, "ignored %s: 0x%x data 0x%llx\n",
- op, msr, data);
+ kvm_pr_unimpl("ignored %s: 0x%x data 0x%llx\n",
+ op, msr, data);
/* Mask the error */
- return 0;
+ return true;
} else {
- vcpu_debug_ratelimited(vcpu, "unhandled %s: 0x%x data 0x%llx\n",
- op, msr, data);
- return -ENOENT;
+ kvm_debug_ratelimited("unhandled %s: 0x%x data 0x%llx\n",
+ op, msr, data);
+ return false;
}
}
@@ -1416,7 +1415,8 @@ static int do_get_msr_feature(struct kvm_vcpu *vcpu, unsigned index, u64 *data)
if (r == KVM_MSR_RET_INVALID) {
/* Unconditionally clear the output for simplicity */
*data = 0;
- r = kvm_msr_ignored_check(vcpu, index, 0, false);
+ if (kvm_msr_ignored_check(vcpu, index, 0, false))
+ r = 0;
}
if (r)
@@ -1540,7 +1540,7 @@ static int __kvm_set_msr(struct kvm_vcpu *vcpu, u32 index, u64 data,
struct msr_data msr;
if (!host_initiated && !kvm_msr_allowed(vcpu, index, KVM_MSR_FILTER_WRITE))
- return -EPERM;
+ return KVM_MSR_RET_FILTERED;
switch (index) {
case MSR_FS_BASE:
@@ -1581,7 +1581,8 @@ static int kvm_set_msr_ignored_check(struct kvm_vcpu *vcpu,
int ret = __kvm_set_msr(vcpu, index, data, host_initiated);
if (ret == KVM_MSR_RET_INVALID)
- ret = kvm_msr_ignored_check(vcpu, index, data, true);
+ if (kvm_msr_ignored_check(vcpu, index, data, true))
+ ret = 0;
return ret;
}
@@ -1599,7 +1600,7 @@ int __kvm_get_msr(struct kvm_vcpu *vcpu, u32 index, u64 *data,
int ret;
if (!host_initiated && !kvm_msr_allowed(vcpu, index, KVM_MSR_FILTER_READ))
- return -EPERM;
+ return KVM_MSR_RET_FILTERED;
msr.index = index;
msr.host_initiated = host_initiated;
@@ -1618,7 +1619,8 @@ static int kvm_get_msr_ignored_check(struct kvm_vcpu *vcpu,
if (ret == KVM_MSR_RET_INVALID) {
/* Unconditionally clear *data for simplicity */
*data = 0;
- ret = kvm_msr_ignored_check(vcpu, index, 0, false);
+ if (kvm_msr_ignored_check(vcpu, index, 0, false))
+ ret = 0;
}
return ret;
@@ -1662,9 +1664,9 @@ static int complete_emulated_wrmsr(struct kvm_vcpu *vcpu)
static u64 kvm_msr_reason(int r)
{
switch (r) {
- case -ENOENT:
+ case KVM_MSR_RET_INVALID:
return KVM_MSR_EXIT_REASON_UNKNOWN;
- case -EPERM:
+ case KVM_MSR_RET_FILTERED:
return KVM_MSR_EXIT_REASON_FILTER;
default:
return KVM_MSR_EXIT_REASON_INVAL;
@@ -1965,7 +1967,7 @@ static void kvm_write_system_time(struct kvm_vcpu *vcpu, gpa_t system_time,
struct kvm_arch *ka = &vcpu->kvm->arch;
if (vcpu->vcpu_id == 0 && !host_initiated) {
- if (ka->boot_vcpu_runs_old_kvmclock && old_msr)
+ if (ka->boot_vcpu_runs_old_kvmclock != old_msr)
kvm_make_request(KVM_REQ_MASTERCLOCK_UPDATE, vcpu);
ka->boot_vcpu_runs_old_kvmclock = old_msr;
@@ -3063,9 +3065,9 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
/* Values other than LBR and BTF are vendor-specific,
thus reserved and should throw a #GP */
return 1;
- }
- vcpu_unimpl(vcpu, "%s: MSR_IA32_DEBUGCTLMSR 0x%llx, nop\n",
- __func__, data);
+ } else if (report_ignored_msrs)
+ vcpu_unimpl(vcpu, "%s: MSR_IA32_DEBUGCTLMSR 0x%llx, nop\n",
+ __func__, data);
break;
case 0x200 ... 0x2ff:
return kvm_mtrr_set_msr(vcpu, msr, data);
@@ -3463,29 +3465,63 @@ int kvm_get_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
msr_info->data = vcpu->arch.efer;
break;
case MSR_KVM_WALL_CLOCK:
+ if (!guest_pv_has(vcpu, KVM_FEATURE_CLOCKSOURCE))
+ return 1;
+
+ msr_info->data = vcpu->kvm->arch.wall_clock;
+ break;
case MSR_KVM_WALL_CLOCK_NEW:
+ if (!guest_pv_has(vcpu, KVM_FEATURE_CLOCKSOURCE2))
+ return 1;
+
msr_info->data = vcpu->kvm->arch.wall_clock;
break;
case MSR_KVM_SYSTEM_TIME:
+ if (!guest_pv_has(vcpu, KVM_FEATURE_CLOCKSOURCE))
+ return 1;
+
+ msr_info->data = vcpu->arch.time;
+ break;
case MSR_KVM_SYSTEM_TIME_NEW:
+ if (!guest_pv_has(vcpu, KVM_FEATURE_CLOCKSOURCE2))
+ return 1;
+
msr_info->data = vcpu->arch.time;
break;
case MSR_KVM_ASYNC_PF_EN:
+ if (!guest_pv_has(vcpu, KVM_FEATURE_ASYNC_PF))
+ return 1;
+
msr_info->data = vcpu->arch.apf.msr_en_val;
break;
case MSR_KVM_ASYNC_PF_INT:
+ if (!guest_pv_has(vcpu, KVM_FEATURE_ASYNC_PF_INT))
+ return 1;
+
msr_info->data = vcpu->arch.apf.msr_int_val;
break;
case MSR_KVM_ASYNC_PF_ACK:
+ if (!guest_pv_has(vcpu, KVM_FEATURE_ASYNC_PF))
+ return 1;
+
msr_info->data = 0;
break;
case MSR_KVM_STEAL_TIME:
+ if (!guest_pv_has(vcpu, KVM_FEATURE_STEAL_TIME))
+ return 1;
+
msr_info->data = vcpu->arch.st.msr_val;
break;
case MSR_KVM_PV_EOI_EN:
+ if (!guest_pv_has(vcpu, KVM_FEATURE_PV_EOI))
+ return 1;
+
msr_info->data = vcpu->arch.pv_eoi.msr_val;
break;
case MSR_KVM_POLL_CONTROL:
+ if (!guest_pv_has(vcpu, KVM_FEATURE_POLL_CONTROL))
+ return 1;
+
msr_info->data = vcpu->arch.msr_kvm_poll_control;
break;
case MSR_IA32_P5_MC_ADDR:
@@ -4575,6 +4611,8 @@ static int kvm_vcpu_ioctl_enable_cap(struct kvm_vcpu *vcpu,
case KVM_CAP_ENFORCE_PV_FEATURE_CPUID:
vcpu->arch.pv_cpuid.enforce = cap->args[0];
+ if (vcpu->arch.pv_cpuid.enforce)
+ kvm_update_pv_runtime(vcpu);
return 0;
diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h
index 3900ab0c6004..e7ca622a468f 100644
--- a/arch/x86/kvm/x86.h
+++ b/arch/x86/kvm/x86.h
@@ -376,7 +376,13 @@ int kvm_handle_memory_failure(struct kvm_vcpu *vcpu, int r,
int kvm_handle_invpcid(struct kvm_vcpu *vcpu, unsigned long type, gva_t gva);
bool kvm_msr_allowed(struct kvm_vcpu *vcpu, u32 index, u32 type);
-#define KVM_MSR_RET_INVALID 2
+/*
+ * Internal error codes that are used to indicate that MSR emulation encountered
+ * an error that should result in #GP in the guest, unless userspace
+ * handles it.
+ */
+#define KVM_MSR_RET_INVALID 2 /* in-kernel MSR emulation #GP condition */
+#define KVM_MSR_RET_FILTERED 3 /* #GP due to userspace MSR filter */
#define __cr4_reserved_bits(__cpu_has, __c) \
({ \