From: Fred Griffoul <fgriffo@amazon.co.uk>
Cache enlightened VMCS control fields to prevent TOCTOU races where the
guest could modify hv_clean_fields or hv_enlightenments_control between
multiple accesses during nested VM-entry.
The cached values ensure consistent behavior across:
- The evmcs-to-vmcs12 copy operations
- MSR bitmap validation
- Clean field checks in prepare_vmcs02_rare()
This eliminates potential guest-induced inconsistencies in nested
virtualization state management.
Signed-off-by: Fred Griffoul <fgriffo@amazon.co.uk>
---
arch/x86/kvm/vmx/hyperv.c | 5 ++--
arch/x86/kvm/vmx/hyperv.h | 20 +++++++++++++
arch/x86/kvm/vmx/nested.c | 62 ++++++++++++++++++++++++---------------
arch/x86/kvm/vmx/vmx.h | 5 +++-
4 files changed, 65 insertions(+), 27 deletions(-)
diff --git a/arch/x86/kvm/vmx/hyperv.c b/arch/x86/kvm/vmx/hyperv.c
index fa41d036acd4..961b91b9bd64 100644
--- a/arch/x86/kvm/vmx/hyperv.c
+++ b/arch/x86/kvm/vmx/hyperv.c
@@ -213,12 +213,11 @@ bool nested_evmcs_l2_tlb_flush_enabled(struct kvm_vcpu *vcpu)
{
struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
struct vcpu_vmx *vmx = to_vmx(vcpu);
- struct hv_enlightened_vmcs *evmcs = vmx->nested.hv_evmcs;
- if (!hv_vcpu || !evmcs)
+ if (!hv_vcpu || !nested_vmx_is_evmptr12_valid(vmx))
return false;
- if (!evmcs->hv_enlightenments_control.nested_flush_hypercall)
+ if (!vmx->nested.hv_flush_hypercall)
return false;
return hv_vcpu->vp_assist_page.nested_control.features.directhypercall;
diff --git a/arch/x86/kvm/vmx/hyperv.h b/arch/x86/kvm/vmx/hyperv.h
index 11a339009781..3c7fea501ca5 100644
--- a/arch/x86/kvm/vmx/hyperv.h
+++ b/arch/x86/kvm/vmx/hyperv.h
@@ -52,6 +52,16 @@ static inline bool guest_cpu_cap_has_evmcs(struct kvm_vcpu *vcpu)
to_vmx(vcpu)->nested.enlightened_vmcs_enabled;
}
+static inline u32 nested_evmcs_clean_fields(struct vcpu_vmx *vmx)
+{
+ return vmx->nested.hv_clean_fields;
+}
+
+static inline bool nested_evmcs_msr_bitmap(struct vcpu_vmx *vmx)
+{
+ return vmx->nested.hv_msr_bitmap;
+}
+
u64 nested_get_evmptr(struct kvm_vcpu *vcpu);
uint16_t nested_get_evmcs_version(struct kvm_vcpu *vcpu);
int nested_enable_evmcs(struct kvm_vcpu *vcpu,
@@ -85,6 +95,16 @@ static inline struct hv_enlightened_vmcs *nested_vmx_evmcs(struct vcpu_vmx *vmx)
{
return NULL;
}
+
+static inline u32 nested_evmcs_clean_fields(struct vcpu_vmx *vmx)
+{
+ return 0;
+}
+
+static inline bool nested_evmcs_msr_bitmap(struct vcpu_vmx *vmx)
+{
+ return false;
+}
#endif
#endif /* __KVM_X86_VMX_HYPERV_H */
diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c
index cb4b85edcb7a..5790e1a26456 100644
--- a/arch/x86/kvm/vmx/nested.c
+++ b/arch/x86/kvm/vmx/nested.c
@@ -236,6 +236,9 @@ static inline void nested_release_evmcs(struct kvm_vcpu *vcpu)
kvm_vcpu_unmap(vcpu, &vmx->nested.hv_evmcs_map);
vmx->nested.hv_evmcs = NULL;
vmx->nested.hv_evmcs_vmptr = EVMPTR_INVALID;
+ vmx->nested.hv_clean_fields = 0;
+ vmx->nested.hv_msr_bitmap = false;
+ vmx->nested.hv_flush_hypercall = false;
if (hv_vcpu) {
hv_vcpu->nested.pa_page_gpa = INVALID_GPA;
@@ -737,10 +740,10 @@ static inline bool nested_vmx_prepare_msr_bitmap(struct kvm_vcpu *vcpu,
* and tells KVM (L0) there were no changes in MSR bitmap for L2.
*/
if (!vmx->nested.force_msr_bitmap_recalc) {
- struct hv_enlightened_vmcs *evmcs = nested_vmx_evmcs(vmx);
-
- if (evmcs && evmcs->hv_enlightenments_control.msr_bitmap &&
- evmcs->hv_clean_fields & HV_VMX_ENLIGHTENED_CLEAN_FIELD_MSR_BITMAP)
+ if (nested_vmx_is_evmptr12_valid(vmx) &&
+ nested_evmcs_msr_bitmap(vmx) &&
+ (nested_evmcs_clean_fields(vmx)
+ & HV_VMX_ENLIGHTENED_CLEAN_FIELD_MSR_BITMAP))
return true;
}
@@ -2214,10 +2217,11 @@ static void copy_vmcs12_to_enlightened(struct vcpu_vmx *vmx)
* instruction.
*/
static enum nested_evmptrld_status nested_vmx_handle_enlightened_vmptrld(
- struct kvm_vcpu *vcpu, bool from_launch)
+ struct kvm_vcpu *vcpu, bool from_launch, bool copy)
{
#ifdef CONFIG_KVM_HYPERV
struct vcpu_vmx *vmx = to_vmx(vcpu);
+ struct hv_enlightened_vmcs *evmcs;
bool evmcs_gpa_changed = false;
u64 evmcs_gpa;
@@ -2297,6 +2301,22 @@ static enum nested_evmptrld_status nested_vmx_handle_enlightened_vmptrld(
vmx->nested.force_msr_bitmap_recalc = true;
}
+ /* Cache evmcs fields to avoid reading evmcs after copy to vmcs12 */
+ evmcs = vmx->nested.hv_evmcs;
+ vmx->nested.hv_clean_fields = evmcs->hv_clean_fields;
+ vmx->nested.hv_flush_hypercall = evmcs->hv_enlightenments_control.nested_flush_hypercall;
+ vmx->nested.hv_msr_bitmap = evmcs->hv_enlightenments_control.msr_bitmap;
+
+ if (copy) {
+ struct vmcs12 *vmcs12 = get_vmcs12(vcpu);
+
+ if (likely(!vmcs12->hdr.shadow_vmcs)) {
+ copy_enlightened_to_vmcs12(vmx, vmx->nested.hv_clean_fields);
+ /* Enlightened VMCS doesn't have launch state */
+ vmcs12->launch_state = !from_launch;
+ }
+ }
+
return EVMPTRLD_SUCCEEDED;
#else
return EVMPTRLD_DISABLED;
@@ -2655,10 +2675,12 @@ static void vmcs_write_cet_state(struct kvm_vcpu *vcpu, u64 s_cet,
static void prepare_vmcs02_rare(struct vcpu_vmx *vmx, struct vmcs12 *vmcs12)
{
- struct hv_enlightened_vmcs *hv_evmcs = nested_vmx_evmcs(vmx);
+ u32 hv_clean_fields = 0;
- if (!hv_evmcs || !(hv_evmcs->hv_clean_fields &
- HV_VMX_ENLIGHTENED_CLEAN_FIELD_GUEST_GRP2)) {
+ if (nested_vmx_is_evmptr12_valid(vmx))
+ hv_clean_fields = nested_evmcs_clean_fields(vmx);
+
+ if (!(hv_clean_fields & HV_VMX_ENLIGHTENED_CLEAN_FIELD_GUEST_GRP2)) {
vmcs_write16(GUEST_ES_SELECTOR, vmcs12->guest_es_selector);
vmcs_write16(GUEST_CS_SELECTOR, vmcs12->guest_cs_selector);
@@ -2700,8 +2722,7 @@ static void prepare_vmcs02_rare(struct vcpu_vmx *vmx, struct vmcs12 *vmcs12)
vmx_segment_cache_clear(vmx);
}
- if (!hv_evmcs || !(hv_evmcs->hv_clean_fields &
- HV_VMX_ENLIGHTENED_CLEAN_FIELD_GUEST_GRP1)) {
+ if (!(hv_clean_fields & HV_VMX_ENLIGHTENED_CLEAN_FIELD_GUEST_GRP1)) {
vmcs_write32(GUEST_SYSENTER_CS, vmcs12->guest_sysenter_cs);
vmcs_writel(GUEST_PENDING_DBG_EXCEPTIONS,
vmcs12->guest_pending_dbg_exceptions);
@@ -2792,7 +2813,7 @@ static int prepare_vmcs02(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12,
enum vm_entry_failure_code *entry_failure_code)
{
struct vcpu_vmx *vmx = to_vmx(vcpu);
- struct hv_enlightened_vmcs *evmcs = nested_vmx_evmcs(vmx);
+ struct hv_enlightened_vmcs *evmcs;
bool load_guest_pdptrs_vmcs12 = false;
if (vmx->nested.dirty_vmcs12 || nested_vmx_is_evmptr12_valid(vmx)) {
@@ -2800,7 +2821,8 @@ static int prepare_vmcs02(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12,
vmx->nested.dirty_vmcs12 = false;
load_guest_pdptrs_vmcs12 = !nested_vmx_is_evmptr12_valid(vmx) ||
- !(evmcs->hv_clean_fields & HV_VMX_ENLIGHTENED_CLEAN_FIELD_GUEST_GRP1);
+ !(nested_evmcs_clean_fields(vmx)
+ & HV_VMX_ENLIGHTENED_CLEAN_FIELD_GUEST_GRP1);
}
if (vmx->nested.nested_run_pending &&
@@ -2929,7 +2951,8 @@ static int prepare_vmcs02(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12,
* bits when it changes a field in eVMCS. Mark all fields as clean
* here.
*/
- if (nested_vmx_is_evmptr12_valid(vmx))
+ evmcs = nested_vmx_evmcs(vmx);
+ if (evmcs)
evmcs->hv_clean_fields |= HV_VMX_ENLIGHTENED_CLEAN_FIELD_ALL;
return 0;
@@ -3477,7 +3500,7 @@ static bool nested_get_evmcs_page(struct kvm_vcpu *vcpu)
if (guest_cpu_cap_has_evmcs(vcpu) &&
vmx->nested.hv_evmcs_vmptr == EVMPTR_MAP_PENDING) {
enum nested_evmptrld_status evmptrld_status =
- nested_vmx_handle_enlightened_vmptrld(vcpu, false);
+ nested_vmx_handle_enlightened_vmptrld(vcpu, false, false);
if (evmptrld_status == EVMPTRLD_VMFAIL ||
evmptrld_status == EVMPTRLD_ERROR)
@@ -3867,7 +3890,7 @@ static int nested_vmx_run(struct kvm_vcpu *vcpu, bool launch)
if (!nested_vmx_check_permission(vcpu))
return 1;
- evmptrld_status = nested_vmx_handle_enlightened_vmptrld(vcpu, launch);
+ evmptrld_status = nested_vmx_handle_enlightened_vmptrld(vcpu, launch, true);
if (evmptrld_status == EVMPTRLD_ERROR) {
kvm_queue_exception(vcpu, UD_VECTOR);
return 1;
@@ -3893,15 +3916,8 @@ static int nested_vmx_run(struct kvm_vcpu *vcpu, bool launch)
if (CC(vmcs12->hdr.shadow_vmcs))
return nested_vmx_failInvalid(vcpu);
- if (nested_vmx_is_evmptr12_valid(vmx)) {
- struct hv_enlightened_vmcs *evmcs = nested_vmx_evmcs(vmx);
-
- copy_enlightened_to_vmcs12(vmx, evmcs->hv_clean_fields);
- /* Enlightened VMCS doesn't have launch state */
- vmcs12->launch_state = !launch;
- } else if (enable_shadow_vmcs) {
+ if (!nested_vmx_is_evmptr12_valid(vmx) && enable_shadow_vmcs)
copy_shadow_to_vmcs12(vmx);
- }
/*
* The nested entry process starts with enforcing various prerequisites
diff --git a/arch/x86/kvm/vmx/vmx.h b/arch/x86/kvm/vmx/vmx.h
index 90fdf130fd85..cda96196c56c 100644
--- a/arch/x86/kvm/vmx/vmx.h
+++ b/arch/x86/kvm/vmx/vmx.h
@@ -205,8 +205,11 @@ struct nested_vmx {
#ifdef CONFIG_KVM_HYPERV
gpa_t hv_evmcs_vmptr;
- struct kvm_host_map hv_evmcs_map;
+ u32 hv_clean_fields;
+ bool hv_msr_bitmap;
+ bool hv_flush_hypercall;
struct hv_enlightened_vmcs *hv_evmcs;
+ struct kvm_host_map hv_evmcs_map;
#endif
};
--
2.43.0Fred Griffoul <griffoul@gmail.com> writes:
> From: Fred Griffoul <fgriffo@amazon.co.uk>
>
> Cache enlightened VMCS control fields to prevent TOCTOU races where the
> guest could modify hv_clean_fields or hv_enlightenments_control between
> multiple accesses during nested VM-entry.
>
> The cached values ensure consistent behavior across:
> - The evmcs-to-vmcs12 copy operations
> - MSR bitmap validation
> - Clean field checks in prepare_vmcs02_rare()
>
> This eliminates potential guest-induced inconsistencies in nested
> virtualization state management.
Could you please split the commit to simplify the review and bughunting
if (when?) issues are discovered? In particular, I would've split this
into at least:
- hv_flush_hypercall caching/handling
- hv_msr_bitmap caching/handling
- nested_vmx_is_evmptr12_valid() instead of vmx->nested.hv_evmcs checks
- adding 'bool copy' argument to nested_vmx_handle_enlightened_vmptrld()
and moving copy_enlightened_to_vmcs12() there from nested_vmx_run()
- hv_clean_fields caching/handling.
I want to be extra careful with clean fields. I may had forgotten the
details since I've implemented it but I still remember some pain over
inconsistent state upon migrations, namely
commit d6bf71a18c74de61548ddad44ff95306fe85f829
Author: Vitaly Kuznetsov <vkuznets@redhat.com>
Date: Wed May 26 15:20:22 2021 +0200
KVM: nVMX: Ignore 'hv_clean_fields' data when eVMCS data is copied in vmx_get_nested_state()
Unfortunatelly, I don't think we have good test coverage for all this in
'hyperv_evmcs' selftest :-( I've seen you added evmcs support to
'vmx_l2_switch_test' in this series, thanks a lot for doing that!
>
> Signed-off-by: Fred Griffoul <fgriffo@amazon.co.uk>
> ---
> arch/x86/kvm/vmx/hyperv.c | 5 ++--
> arch/x86/kvm/vmx/hyperv.h | 20 +++++++++++++
> arch/x86/kvm/vmx/nested.c | 62 ++++++++++++++++++++++++---------------
> arch/x86/kvm/vmx/vmx.h | 5 +++-
> 4 files changed, 65 insertions(+), 27 deletions(-)
>
> diff --git a/arch/x86/kvm/vmx/hyperv.c b/arch/x86/kvm/vmx/hyperv.c
> index fa41d036acd4..961b91b9bd64 100644
> --- a/arch/x86/kvm/vmx/hyperv.c
> +++ b/arch/x86/kvm/vmx/hyperv.c
> @@ -213,12 +213,11 @@ bool nested_evmcs_l2_tlb_flush_enabled(struct kvm_vcpu *vcpu)
> {
> struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
> struct vcpu_vmx *vmx = to_vmx(vcpu);
> - struct hv_enlightened_vmcs *evmcs = vmx->nested.hv_evmcs;
>
> - if (!hv_vcpu || !evmcs)
> + if (!hv_vcpu || !nested_vmx_is_evmptr12_valid(vmx))
> return false;
>
> - if (!evmcs->hv_enlightenments_control.nested_flush_hypercall)
> + if (!vmx->nested.hv_flush_hypercall)
> return false;
>
> return hv_vcpu->vp_assist_page.nested_control.features.directhypercall;
> diff --git a/arch/x86/kvm/vmx/hyperv.h b/arch/x86/kvm/vmx/hyperv.h
> index 11a339009781..3c7fea501ca5 100644
> --- a/arch/x86/kvm/vmx/hyperv.h
> +++ b/arch/x86/kvm/vmx/hyperv.h
> @@ -52,6 +52,16 @@ static inline bool guest_cpu_cap_has_evmcs(struct kvm_vcpu *vcpu)
> to_vmx(vcpu)->nested.enlightened_vmcs_enabled;
> }
>
> +static inline u32 nested_evmcs_clean_fields(struct vcpu_vmx *vmx)
> +{
> + return vmx->nested.hv_clean_fields;
> +}
> +
> +static inline bool nested_evmcs_msr_bitmap(struct vcpu_vmx *vmx)
> +{
> + return vmx->nested.hv_msr_bitmap;
> +}
> +
> u64 nested_get_evmptr(struct kvm_vcpu *vcpu);
> uint16_t nested_get_evmcs_version(struct kvm_vcpu *vcpu);
> int nested_enable_evmcs(struct kvm_vcpu *vcpu,
> @@ -85,6 +95,16 @@ static inline struct hv_enlightened_vmcs *nested_vmx_evmcs(struct vcpu_vmx *vmx)
> {
> return NULL;
> }
> +
> +static inline u32 nested_evmcs_clean_fields(struct vcpu_vmx *vmx)
> +{
> + return 0;
> +}
> +
> +static inline bool nested_evmcs_msr_bitmap(struct vcpu_vmx *vmx)
> +{
> + return false;
> +}
> #endif
>
> #endif /* __KVM_X86_VMX_HYPERV_H */
> diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c
> index cb4b85edcb7a..5790e1a26456 100644
> --- a/arch/x86/kvm/vmx/nested.c
> +++ b/arch/x86/kvm/vmx/nested.c
> @@ -236,6 +236,9 @@ static inline void nested_release_evmcs(struct kvm_vcpu *vcpu)
> kvm_vcpu_unmap(vcpu, &vmx->nested.hv_evmcs_map);
> vmx->nested.hv_evmcs = NULL;
> vmx->nested.hv_evmcs_vmptr = EVMPTR_INVALID;
> + vmx->nested.hv_clean_fields = 0;
> + vmx->nested.hv_msr_bitmap = false;
> + vmx->nested.hv_flush_hypercall = false;
>
> if (hv_vcpu) {
> hv_vcpu->nested.pa_page_gpa = INVALID_GPA;
> @@ -737,10 +740,10 @@ static inline bool nested_vmx_prepare_msr_bitmap(struct kvm_vcpu *vcpu,
> * and tells KVM (L0) there were no changes in MSR bitmap for L2.
> */
> if (!vmx->nested.force_msr_bitmap_recalc) {
> - struct hv_enlightened_vmcs *evmcs = nested_vmx_evmcs(vmx);
> -
> - if (evmcs && evmcs->hv_enlightenments_control.msr_bitmap &&
> - evmcs->hv_clean_fields & HV_VMX_ENLIGHTENED_CLEAN_FIELD_MSR_BITMAP)
> + if (nested_vmx_is_evmptr12_valid(vmx) &&
> + nested_evmcs_msr_bitmap(vmx) &&
> + (nested_evmcs_clean_fields(vmx)
> + & HV_VMX_ENLIGHTENED_CLEAN_FIELD_MSR_BITMAP))
> return true;
> }
>
> @@ -2214,10 +2217,11 @@ static void copy_vmcs12_to_enlightened(struct vcpu_vmx *vmx)
> * instruction.
> */
> static enum nested_evmptrld_status nested_vmx_handle_enlightened_vmptrld(
> - struct kvm_vcpu *vcpu, bool from_launch)
> + struct kvm_vcpu *vcpu, bool from_launch, bool copy)
> {
> #ifdef CONFIG_KVM_HYPERV
> struct vcpu_vmx *vmx = to_vmx(vcpu);
> + struct hv_enlightened_vmcs *evmcs;
> bool evmcs_gpa_changed = false;
> u64 evmcs_gpa;
>
> @@ -2297,6 +2301,22 @@ static enum nested_evmptrld_status nested_vmx_handle_enlightened_vmptrld(
> vmx->nested.force_msr_bitmap_recalc = true;
> }
>
> + /* Cache evmcs fields to avoid reading evmcs after copy to vmcs12 */
> + evmcs = vmx->nested.hv_evmcs;
> + vmx->nested.hv_clean_fields = evmcs->hv_clean_fields;
> + vmx->nested.hv_flush_hypercall = evmcs->hv_enlightenments_control.nested_flush_hypercall;
> + vmx->nested.hv_msr_bitmap = evmcs->hv_enlightenments_control.msr_bitmap;
> +
> + if (copy) {
> + struct vmcs12 *vmcs12 = get_vmcs12(vcpu);
> +
> + if (likely(!vmcs12->hdr.shadow_vmcs)) {
> + copy_enlightened_to_vmcs12(vmx, vmx->nested.hv_clean_fields);
> + /* Enlightened VMCS doesn't have launch state */
> + vmcs12->launch_state = !from_launch;
> + }
> + }
> +
> return EVMPTRLD_SUCCEEDED;
> #else
> return EVMPTRLD_DISABLED;
> @@ -2655,10 +2675,12 @@ static void vmcs_write_cet_state(struct kvm_vcpu *vcpu, u64 s_cet,
>
> static void prepare_vmcs02_rare(struct vcpu_vmx *vmx, struct vmcs12 *vmcs12)
> {
> - struct hv_enlightened_vmcs *hv_evmcs = nested_vmx_evmcs(vmx);
> + u32 hv_clean_fields = 0;
>
> - if (!hv_evmcs || !(hv_evmcs->hv_clean_fields &
> - HV_VMX_ENLIGHTENED_CLEAN_FIELD_GUEST_GRP2)) {
> + if (nested_vmx_is_evmptr12_valid(vmx))
> + hv_clean_fields = nested_evmcs_clean_fields(vmx);
> +
> + if (!(hv_clean_fields & HV_VMX_ENLIGHTENED_CLEAN_FIELD_GUEST_GRP2)) {
>
> vmcs_write16(GUEST_ES_SELECTOR, vmcs12->guest_es_selector);
> vmcs_write16(GUEST_CS_SELECTOR, vmcs12->guest_cs_selector);
> @@ -2700,8 +2722,7 @@ static void prepare_vmcs02_rare(struct vcpu_vmx *vmx, struct vmcs12 *vmcs12)
> vmx_segment_cache_clear(vmx);
> }
>
> - if (!hv_evmcs || !(hv_evmcs->hv_clean_fields &
> - HV_VMX_ENLIGHTENED_CLEAN_FIELD_GUEST_GRP1)) {
> + if (!(hv_clean_fields & HV_VMX_ENLIGHTENED_CLEAN_FIELD_GUEST_GRP1)) {
> vmcs_write32(GUEST_SYSENTER_CS, vmcs12->guest_sysenter_cs);
> vmcs_writel(GUEST_PENDING_DBG_EXCEPTIONS,
> vmcs12->guest_pending_dbg_exceptions);
> @@ -2792,7 +2813,7 @@ static int prepare_vmcs02(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12,
> enum vm_entry_failure_code *entry_failure_code)
> {
> struct vcpu_vmx *vmx = to_vmx(vcpu);
> - struct hv_enlightened_vmcs *evmcs = nested_vmx_evmcs(vmx);
> + struct hv_enlightened_vmcs *evmcs;
> bool load_guest_pdptrs_vmcs12 = false;
>
> if (vmx->nested.dirty_vmcs12 || nested_vmx_is_evmptr12_valid(vmx)) {
> @@ -2800,7 +2821,8 @@ static int prepare_vmcs02(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12,
> vmx->nested.dirty_vmcs12 = false;
>
> load_guest_pdptrs_vmcs12 = !nested_vmx_is_evmptr12_valid(vmx) ||
> - !(evmcs->hv_clean_fields & HV_VMX_ENLIGHTENED_CLEAN_FIELD_GUEST_GRP1);
> + !(nested_evmcs_clean_fields(vmx)
> + & HV_VMX_ENLIGHTENED_CLEAN_FIELD_GUEST_GRP1);
> }
>
> if (vmx->nested.nested_run_pending &&
> @@ -2929,7 +2951,8 @@ static int prepare_vmcs02(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12,
> * bits when it changes a field in eVMCS. Mark all fields as clean
> * here.
> */
> - if (nested_vmx_is_evmptr12_valid(vmx))
> + evmcs = nested_vmx_evmcs(vmx);
> + if (evmcs)
> evmcs->hv_clean_fields |= HV_VMX_ENLIGHTENED_CLEAN_FIELD_ALL;
>
> return 0;
> @@ -3477,7 +3500,7 @@ static bool nested_get_evmcs_page(struct kvm_vcpu *vcpu)
> if (guest_cpu_cap_has_evmcs(vcpu) &&
> vmx->nested.hv_evmcs_vmptr == EVMPTR_MAP_PENDING) {
> enum nested_evmptrld_status evmptrld_status =
> - nested_vmx_handle_enlightened_vmptrld(vcpu, false);
> + nested_vmx_handle_enlightened_vmptrld(vcpu, false, false);
>
> if (evmptrld_status == EVMPTRLD_VMFAIL ||
> evmptrld_status == EVMPTRLD_ERROR)
> @@ -3867,7 +3890,7 @@ static int nested_vmx_run(struct kvm_vcpu *vcpu, bool launch)
> if (!nested_vmx_check_permission(vcpu))
> return 1;
>
> - evmptrld_status = nested_vmx_handle_enlightened_vmptrld(vcpu, launch);
> + evmptrld_status = nested_vmx_handle_enlightened_vmptrld(vcpu, launch, true);
> if (evmptrld_status == EVMPTRLD_ERROR) {
> kvm_queue_exception(vcpu, UD_VECTOR);
> return 1;
> @@ -3893,15 +3916,8 @@ static int nested_vmx_run(struct kvm_vcpu *vcpu, bool launch)
> if (CC(vmcs12->hdr.shadow_vmcs))
> return nested_vmx_failInvalid(vcpu);
>
> - if (nested_vmx_is_evmptr12_valid(vmx)) {
> - struct hv_enlightened_vmcs *evmcs = nested_vmx_evmcs(vmx);
> -
> - copy_enlightened_to_vmcs12(vmx, evmcs->hv_clean_fields);
> - /* Enlightened VMCS doesn't have launch state */
> - vmcs12->launch_state = !launch;
> - } else if (enable_shadow_vmcs) {
> + if (!nested_vmx_is_evmptr12_valid(vmx) && enable_shadow_vmcs)
> copy_shadow_to_vmcs12(vmx);
> - }
>
> /*
> * The nested entry process starts with enforcing various prerequisites
> diff --git a/arch/x86/kvm/vmx/vmx.h b/arch/x86/kvm/vmx/vmx.h
> index 90fdf130fd85..cda96196c56c 100644
> --- a/arch/x86/kvm/vmx/vmx.h
> +++ b/arch/x86/kvm/vmx/vmx.h
> @@ -205,8 +205,11 @@ struct nested_vmx {
>
> #ifdef CONFIG_KVM_HYPERV
> gpa_t hv_evmcs_vmptr;
> - struct kvm_host_map hv_evmcs_map;
> + u32 hv_clean_fields;
> + bool hv_msr_bitmap;
> + bool hv_flush_hypercall;
> struct hv_enlightened_vmcs *hv_evmcs;
> + struct kvm_host_map hv_evmcs_map;
> #endif
> };
--
Vitaly
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