[PATCH v3 7/8] nSVM: use vmcb_ctrl_area_cached instead of vmcb_control_area in struct svm_nested_state

Emanuele Giuseppe Esposito
2021-10-11T14:39:02Z

This requires changing all vmcb_is_intercept(&svm->nested.ctl, ...)
calls with vmcb12_is_intercept().

In addition, in svm_get_nested_state() user space expects a
vmcb_control_area struct, so we need to copy back all fields
in a temporary structure to provide to the user space.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
---
arch/x86/kvm/svm/nested.c | 41 +++++++++++++++++++++++----------------
arch/x86/kvm/svm/svm.c | 4 ++--
arch/x86/kvm/svm/svm.h | 8 ++++----
3 files changed, 30 insertions(+), 23 deletions(-)

diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c
index c84cded1dcf6..13be1002ad1c 100644
--- a/arch/x86/kvm/svm/nested.c
+++ b/arch/x86/kvm/svm/nested.c
@@ -58,8 +58,9 @@ static void svm_inject_page_fault_nested(struct kvm_vcpu *vcpu, struct x86_excep
struct vcpu_svm *svm = to_svm(vcpu);
WARN_ON(!is_guest_mode(vcpu));

- if (vmcb_is_intercept(&svm->nested.ctl, INTERCEPT_EXCEPTION_OFFSET + PF_VECTOR) &&
- !svm->nested.nested_run_pending) {
+ if (vmcb12_is_intercept(&svm->nested.ctl,
+ INTERCEPT_EXCEPTION_OFFSET + PF_VECTOR) &&
+ !svm->nested.nested_run_pending) {
svm->vmcb->control.exit_code = SVM_EXIT_EXCP_BASE + PF_VECTOR;
svm->vmcb->control.exit_code_hi = 0;
svm->vmcb->control.exit_info_1 = fault->error_code;
@@ -121,7 +122,8 @@ static void nested_svm_uninit_mmu_context(struct kvm_vcpu *vcpu)

void recalc_intercepts(struct vcpu_svm *svm)
{
- struct vmcb_control_area *c, *h, *g;
+ struct vmcb_control_area *c, *h;
+ struct vmcb_ctrl_area_cached *g;
unsigned int i;

vmcb_mark_dirty(svm->vmcb, VMCB_INTERCEPTS);
@@ -172,7 +174,7 @@ static bool nested_svm_vmrun_msrpm(struct vcpu_svm *svm)
*/
int i;

- if (!(vmcb_is_intercept(&svm->nested.ctl, INTERCEPT_MSR_PROT)))
+ if (!(vmcb12_is_intercept(&svm->nested.ctl, INTERCEPT_MSR_PROT)))
return true;

for (i = 0; i < MSRPM_OFFSETS; i++) {
@@ -208,9 +210,9 @@ static bool nested_svm_check_bitmap_pa(struct kvm_vcpu *vcpu, u64 pa, u32 size)
}

static bool nested_vmcb_check_controls(struct kvm_vcpu *vcpu,
- struct vmcb_control_area *control)
+ struct vmcb_ctrl_area_cached *control)
{
- if (CC(!vmcb_is_intercept(control, INTERCEPT_VMRUN)))
+ if (CC(!vmcb12_is_intercept(control, INTERCEPT_VMRUN)))
return false;

if (CC(control->asid == 0))
@@ -960,7 +962,7 @@ static int nested_svm_exit_handled_msr(struct vcpu_svm *svm)
u32 offset, msr, value;
int write, mask;

- if (!(vmcb_is_intercept(&svm->nested.ctl, INTERCEPT_MSR_PROT)))
+ if (!(vmcb12_is_intercept(&svm->nested.ctl, INTERCEPT_MSR_PROT)))
return NESTED_EXIT_HOST;

msr = svm->vcpu.arch.regs[VCPU_REGS_RCX];
@@ -987,7 +989,7 @@ static int nested_svm_intercept_ioio(struct vcpu_svm *svm)
u8 start_bit;
u64 gpa;

- if (!(vmcb_is_intercept(&svm->nested.ctl, INTERCEPT_IOIO_PROT)))
+ if (!(vmcb12_is_intercept(&svm->nested.ctl, INTERCEPT_IOIO_PROT)))
return NESTED_EXIT_HOST;

port = svm->vmcb->control.exit_info_1 >> 16;
@@ -1018,12 +1020,12 @@ static int nested_svm_intercept(struct vcpu_svm *svm)
vmexit = nested_svm_intercept_ioio(svm);
break;
case SVM_EXIT_READ_CR0 ... SVM_EXIT_WRITE_CR8: {
- if (vmcb_is_intercept(&svm->nested.ctl, exit_code))
+ if (vmcb12_is_intercept(&svm->nested.ctl, exit_code))
vmexit = NESTED_EXIT_DONE;
break;
}
case SVM_EXIT_READ_DR0 ... SVM_EXIT_WRITE_DR7: {
- if (vmcb_is_intercept(&svm->nested.ctl, exit_code))
+ if (vmcb12_is_intercept(&svm->nested.ctl, exit_code))
vmexit = NESTED_EXIT_DONE;
break;
}
@@ -1041,7 +1043,7 @@ static int nested_svm_intercept(struct vcpu_svm *svm)
break;
}
default: {
- if (vmcb_is_intercept(&svm->nested.ctl, exit_code))
+ if (vmcb12_is_intercept(&svm->nested.ctl, exit_code))
vmexit = NESTED_EXIT_DONE;
}
}
@@ -1119,7 +1121,7 @@ static void nested_svm_inject_exception_vmexit(struct vcpu_svm *svm)

static inline bool nested_exit_on_init(struct vcpu_svm *svm)
{
- return vmcb_is_intercept(&svm->nested.ctl, INTERCEPT_INIT);
+ return vmcb12_is_intercept(&svm->nested.ctl, INTERCEPT_INIT);
}

static int svm_check_nested_events(struct kvm_vcpu *vcpu)
@@ -1250,6 +1252,7 @@ static int svm_get_nested_state(struct kvm_vcpu *vcpu,
u32 user_data_size)
{
struct vcpu_svm *svm;
+ struct vmcb_control_area ctl_temp;
struct kvm_nested_state kvm_state = {
.flags = 0,
.format = KVM_STATE_NESTED_FORMAT_SVM,
@@ -1291,7 +1294,8 @@ static int svm_get_nested_state(struct kvm_vcpu *vcpu,
*/
if (clear_user(user_vmcb, KVM_STATE_NESTED_SVM_VMCB_SIZE))
return -EFAULT;
- if (copy_to_user(&user_vmcb->control, &svm->nested.ctl,
+ nested_copy_vmcb_cache_to_control(&ctl_temp, &svm->nested.ctl);
+ if (copy_to_user(&user_vmcb->control, &ctl_temp,
sizeof(user_vmcb->control)))
return -EFAULT;
if (copy_to_user(&user_vmcb->save, &svm->vmcb01.ptr->save,
@@ -1362,8 +1366,9 @@ static int svm_set_nested_state(struct kvm_vcpu *vcpu,
goto out_free;

ret = -EINVAL;
- if (!nested_vmcb_check_controls(vcpu, ctl))
- goto out_free;
+ nested_copy_vmcb_control_to_cache(svm, ctl);
+ if (!nested_vmcb_check_controls(vcpu, &svm->nested.ctl))
+ goto out_free_ctl;

/*
* Processor state contains L2 state. Check that it is
@@ -1371,7 +1376,7 @@ static int svm_set_nested_state(struct kvm_vcpu *vcpu,
*/
cr0 = kvm_read_cr0(vcpu);
if (((cr0 & X86_CR0_CD) == 0) && (cr0 & X86_CR0_NW))
- goto out_free;
+ goto out_free_ctl;

/*
* Validate host state saved from before VMRUN (see
@@ -1417,7 +1422,6 @@ static int svm_set_nested_state(struct kvm_vcpu *vcpu,
svm->nested.vmcb12_gpa = kvm_state->hdr.svm.vmcb_pa;

svm_copy_vmrun_state(&svm->vmcb01.ptr->save, save);
- nested_copy_vmcb_control_to_cache(svm, ctl);

svm_switch_vmcb(svm, &svm->nested.vmcb02);
nested_vmcb02_prepare_control(svm);
@@ -1427,6 +1431,9 @@ static int svm_set_nested_state(struct kvm_vcpu *vcpu,
out_free_save:
memset(&svm->nested.save, 0, sizeof(struct vmcb_save_area_cached));

+out_free_ctl:
+ memset(&svm->nested.ctl, 0, sizeof(struct vmcb_ctrl_area_cached));
+
out_free:
kfree(save);
kfree(ctl);
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index 1b6d25c6e0ae..d866eea39777 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -2465,7 +2465,7 @@ static bool check_selective_cr0_intercepted(struct kvm_vcpu *vcpu,
bool ret = false;

if (!is_guest_mode(vcpu) ||
- (!(vmcb_is_intercept(&svm->nested.ctl, INTERCEPT_SELECTIVE_CR0))))
+ (!(vmcb12_is_intercept(&svm->nested.ctl, INTERCEPT_SELECTIVE_CR0))))
return false;

cr0 &= ~SVM_CR0_SELECTIVE_MASK;
@@ -4184,7 +4184,7 @@ static int svm_check_intercept(struct kvm_vcpu *vcpu,
info->intercept == x86_intercept_clts)
break;

- if (!(vmcb_is_intercept(&svm->nested.ctl,
+ if (!(vmcb12_is_intercept(&svm->nested.ctl,
INTERCEPT_SELECTIVE_CR0)))
break;

diff --git a/arch/x86/kvm/svm/svm.h b/arch/x86/kvm/svm/svm.h
index 78006245e334..051b7d0a13a1 100644
--- a/arch/x86/kvm/svm/svm.h
+++ b/arch/x86/kvm/svm/svm.h
@@ -156,7 +156,7 @@ struct svm_nested_state {
bool nested_run_pending;

/* cache for control fields of the guest */
- struct vmcb_control_area ctl;
+ struct vmcb_ctrl_area_cached ctl;
struct vmcb_save_area_cached save;

bool initialized;
@@ -491,17 +491,17 @@ static inline bool nested_svm_virtualize_tpr(struct kvm_vcpu *vcpu)

static inline bool nested_exit_on_smi(struct vcpu_svm *svm)
{
- return vmcb_is_intercept(&svm->nested.ctl, INTERCEPT_SMI);
+ return vmcb12_is_intercept(&svm->nested.ctl, INTERCEPT_SMI);
}

static inline bool nested_exit_on_intr(struct vcpu_svm *svm)
{
- return vmcb_is_intercept(&svm->nested.ctl, INTERCEPT_INTR);
+ return vmcb12_is_intercept(&svm->nested.ctl, INTERCEPT_INTR);
}

static inline bool nested_exit_on_nmi(struct vcpu_svm *svm)
{
- return vmcb_is_intercept(&svm->nested.ctl, INTERCEPT_NMI);
+ return vmcb12_is_intercept(&svm->nested.ctl, INTERCEPT_NMI);
}

int enter_svm_guest_mode(struct kvm_vcpu *vcpu, u64 vmcb_gpa, struct vmcb *vmcb12);
--
2.27.0