[PATCH 4/7] KVM: SVM: save all control fields in svm->nested

[Paolo Bonzini]

In preparation for nested SVM save/restore, store all data that matters
from the VMCB control area into svm->nested.  It will then become part
of the nested SVM state that is saved by KVM_SET_NESTED_STATE and
restored by KVM_GET_NESTED_STATE, just like the cached vmcs12 for nVMX.

Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
---
 arch/x86/kvm/svm/nested.c | 37 ++++++++++++++++++++++---------------
 arch/x86/kvm/svm/svm.c    |  6 ++++++
 arch/x86/kvm/svm/svm.h    | 22 ++++++++++++++++------
 3 files changed, 44 insertions(+), 21 deletions(-)

diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c
index 7807f6cc01fc..54be341322d8 100644
--- a/arch/x86/kvm/svm/nested.c
+++ b/arch/x86/kvm/svm/nested.c
@@ -237,7 +237,16 @@ static void load_nested_vmcb_control(struct vcpu_svm *svm, struct vmcb *nested_v
 	svm->nested.vmcb_msrpm = nested_vmcb->control.msrpm_base_pa & ~0x0fffULL;
 	svm->nested.vmcb_iopm  = nested_vmcb->control.iopm_base_pa  & ~0x0fffULL;
 
-	/* cache intercepts */
+	svm->nested.nested_ctl           = nested_vmcb->control.nested_ctl;
+	svm->nested.int_ctl              = nested_vmcb->control.int_ctl;
+	svm->nested.virt_ext             = nested_vmcb->control.virt_ext;
+	svm->nested.int_vector           = nested_vmcb->control.int_vector;
+	svm->nested.int_state            = nested_vmcb->control.int_state;
+	svm->nested.event_inj     	 = nested_vmcb->control.event_inj;
+	svm->nested.event_inj_err 	 = nested_vmcb->control.event_inj_err;
+	svm->nested.pause_filter_count   = nested_vmcb->control.pause_filter_count;
+	svm->nested.pause_filter_thresh  = nested_vmcb->control.pause_filter_thresh;
+
 	svm->nested.intercept_cr         = nested_vmcb->control.intercept_cr;
 	svm->nested.intercept_dr         = nested_vmcb->control.intercept_dr;
 	svm->nested.intercept_exceptions = nested_vmcb->control.intercept_exceptions;
@@ -279,33 +288,31 @@ static void load_nested_vmcb_save(struct vcpu_svm *svm, struct vmcb *nested_vmcb
 	svm->vmcb->save.cpl = nested_vmcb->save.cpl;
 }
 
-static void nested_prepare_vmcb_control(struct vcpu_svm *svm, struct vmcb *nested_vmcb)
+static void nested_prepare_vmcb_control(struct vcpu_svm *svm)
 {
-	if (nested_vmcb->control.nested_ctl & SVM_NESTED_CTL_NP_ENABLE)
+	if (svm->nested.nested_ctl & SVM_NESTED_CTL_NP_ENABLE)
 		nested_svm_init_mmu_context(&svm->vcpu);
 
 	/* Guest paging mode is active - reset mmu */
 	kvm_mmu_reset_context(&svm->vcpu);
 
 	svm_flush_tlb(&svm->vcpu);
-	if (nested_vmcb->control.int_ctl & V_INTR_MASKING_MASK)
+	if (svm->nested.int_ctl & V_INTR_MASKING_MASK)
 		svm->vcpu.arch.hflags |= HF_VINTR_MASK;
 	else
 		svm->vcpu.arch.hflags &= ~HF_VINTR_MASK;
 
 	svm->vmcb->control.tsc_offset = svm->vcpu.arch.tsc_offset;
 
-	svm->vmcb->control.int_ctl = nested_vmcb->control.int_ctl | V_INTR_MASKING_MASK;
-	svm->vmcb->control.virt_ext = nested_vmcb->control.virt_ext;
-	svm->vmcb->control.int_vector = nested_vmcb->control.int_vector;
-	svm->vmcb->control.int_state = nested_vmcb->control.int_state;
-	svm->vmcb->control.event_inj = nested_vmcb->control.event_inj;
-	svm->vmcb->control.event_inj_err = nested_vmcb->control.event_inj_err;
+	svm->vmcb->control.int_ctl             = svm->nested.int_ctl | V_INTR_MASKING_MASK;
+	svm->vmcb->control.virt_ext            = svm->nested.virt_ext;
+	svm->vmcb->control.int_vector          = svm->nested.int_vector;
+	svm->vmcb->control.int_state           = svm->nested.int_state;
+	svm->vmcb->control.event_inj           = svm->nested.event_inj;
+	svm->vmcb->control.event_inj_err       = svm->nested.event_inj_err;
 
-	svm->vmcb->control.pause_filter_count =
-		nested_vmcb->control.pause_filter_count;
-	svm->vmcb->control.pause_filter_thresh =
-		nested_vmcb->control.pause_filter_thresh;
+	svm->vmcb->control.pause_filter_count  = svm->nested.pause_filter_count;
+	svm->vmcb->control.pause_filter_thresh = svm->nested.pause_filter_thresh;
 
 	/* Enter Guest-Mode */
 	enter_guest_mode(&svm->vcpu);
@@ -329,7 +336,7 @@ void enter_svm_guest_mode(struct vcpu_svm *svm, u64 vmcb_gpa,
 	svm->nested.vmcb = vmcb_gpa;
 	load_nested_vmcb_control(svm, nested_vmcb);
 	load_nested_vmcb_save(svm, nested_vmcb);
-	nested_prepare_vmcb_control(svm, nested_vmcb);
+	nested_prepare_vmcb_control(svm);
 
 	/*
 	 * If L1 had a pending IRQ/NMI before executing VMRUN,
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index dc12a03d16f6..2b63d15328ba 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -3343,6 +3343,12 @@ static fastpath_t svm_vcpu_run(struct kvm_vcpu *vcpu)
 	if (unlikely(svm->nested.exit_required))
 		return EXIT_FASTPATH_NONE;
 
+	if (unlikely(svm->nested.nested_run_pending)) {
+		/* After this vmentry, these fields will be used up.  */
+		svm->nested.event_inj     = 0;
+		svm->nested.event_inj_err = 0;
+	}
+
 	/*
 	 * Disable singlestep if we're injecting an interrupt/exception.
 	 * We don't want our modified rflags to be pushed on the stack where
diff --git a/arch/x86/kvm/svm/svm.h b/arch/x86/kvm/svm/svm.h
index 730eb7242930..5cabed9c733a 100644
--- a/arch/x86/kvm/svm/svm.h
+++ b/arch/x86/kvm/svm/svm.h
@@ -90,10 +90,6 @@ struct nested_state {
 	/* These are the merged vectors */
 	u32 *msrpm;
 
-	/* gpa pointers to the real vectors */
-	u64 vmcb_msrpm;
-	u64 vmcb_iopm;
-
 	/* A VMEXIT is required but not yet emulated */
 	bool exit_required;
 
@@ -101,13 +97,27 @@ struct nested_state {
 	 * we cannot inject a nested vmexit yet.  */
 	bool nested_run_pending;
 
-	/* cache for intercepts of the guest */
+	/* cache for control fields of the guest */
+	u64 vmcb_msrpm;
+	u64 vmcb_iopm;
+
 	u32 intercept_cr;
 	u32 intercept_dr;
 	u32 intercept_exceptions;
 	u64 intercept;
 
-	/* Nested Paging related state */
+	u32 event_inj;
+	u32 event_inj_err;
+
+	u64 virt_ext;
+	u32 int_ctl;
+	u32 int_vector;
+	u32 int_state;
+
+	u16 pause_filter_thresh;
+	u16 pause_filter_count;
+
+	u64 nested_ctl;
 	u64 nested_cr3;
 };
 
-- 
2.18.2