4 files changed, 65 insertions, 5 deletions

diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c
index 486c7ac6d813..bcca0b80e0d0 100644
--- a/arch/x86/kvm/vmx/nested.c
+++ b/arch/x86/kvm/vmx/nested.c
@@ -4490,6 +4490,11 @@ void nested_vmx_vmexit(struct kvm_vcpu *vcpu, u32 vm_exit_reason,
 		vmx_set_virtual_apic_mode(vcpu);
 	}
 
+	if (vmx->nested.update_vmcs01_cpu_dirty_logging) {
+		vmx->nested.update_vmcs01_cpu_dirty_logging = false;
+		vmx_update_cpu_dirty_logging(vcpu);
+	}
+
 	/* Unpin physical memory we referred to in vmcs02 */
 	if (vmx->nested.apic_access_page) {
 		kvm_release_page_clean(vmx->nested.apic_access_page);
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index eb207ffb7873..50810d471462 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -4277,7 +4277,12 @@ static void vmx_compute_secondary_exec_control(struct vcpu_vmx *vmx)
 	*/
 	exec_control &= ~SECONDARY_EXEC_SHADOW_VMCS;
 
-	if (!enable_pml)
+	/*
+	 * PML is enabled/disabled when dirty logging of memsmlots changes, but
+	 * it needs to be set here when dirty logging is already active, e.g.
+	 * if this vCPU was created after dirty logging was enabled.
+	 */
+	if (!vcpu->kvm->arch.cpu_dirty_logging_count)
 		exec_control &= ~SECONDARY_EXEC_ENABLE_PML;
 
 	if (cpu_has_vmx_xsaves()) {
@@ -7491,6 +7496,26 @@ static void vmx_sched_in(struct kvm_vcpu *vcpu, int cpu)
 		shrink_ple_window(vcpu);
 }
 
+void vmx_update_cpu_dirty_logging(struct kvm_vcpu *vcpu)
+{
+	struct vcpu_vmx *vmx = to_vmx(vcpu);
+
+	if (is_guest_mode(vcpu)) {
+		vmx->nested.update_vmcs01_cpu_dirty_logging = true;
+		return;
+	}
+
+	/*
+	 * Note, cpu_dirty_logging_count can be changed concurrent with this
+	 * code, but in that case another update request will be made and so
+	 * the guest will never run with a stale PML value.
+	 */
+	if (vcpu->kvm->arch.cpu_dirty_logging_count)
+		secondary_exec_controls_setbit(vmx, SECONDARY_EXEC_ENABLE_PML);
+	else
+		secondary_exec_controls_clearbit(vmx, SECONDARY_EXEC_ENABLE_PML);
+}
+
 static int vmx_pre_block(struct kvm_vcpu *vcpu)
 {
 	if (pi_pre_block(vcpu))
@@ -7698,6 +7723,7 @@ static struct kvm_x86_ops vmx_x86_ops __initdata = {
 	.sched_in = vmx_sched_in,
 
 	.cpu_dirty_log_size = PML_ENTITY_NUM,
+	.update_cpu_dirty_logging = vmx_update_cpu_dirty_logging,
 
 	.pre_block = vmx_pre_block,
 	.post_block = vmx_post_block,
diff --git a/arch/x86/kvm/vmx/vmx.h b/arch/x86/kvm/vmx/vmx.h
index 12c53d05a902..89da5e1251f1 100644
--- a/arch/x86/kvm/vmx/vmx.h
+++ b/arch/x86/kvm/vmx/vmx.h
@@ -165,6 +165,7 @@ struct nested_vmx {
 
 	bool change_vmcs01_virtual_apic_mode;
 	bool reload_vmcs01_apic_access_page;
+	bool update_vmcs01_cpu_dirty_logging;
 
 	/*
 	 * Enlightened VMCS has been enabled. It does not mean that L1 has to
@@ -393,6 +394,7 @@ int vmx_find_loadstore_msr_slot(struct vmx_msrs *m, u32 msr);
 void vmx_ept_load_pdptrs(struct kvm_vcpu *vcpu);
 void vmx_set_intercept_for_msr(struct kvm_vcpu *vcpu,
 	u32 msr, int type, bool value);
+void vmx_update_cpu_dirty_logging(struct kvm_vcpu *vcpu);
 
 static inline u8 vmx_get_rvi(void)
 {
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index c0d22f19aed0..b9a8c8af9713 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -8987,6 +8987,9 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
 			kvm_check_async_pf_completion(vcpu);
 		if (kvm_check_request(KVM_REQ_MSR_FILTER_CHANGED, vcpu))
 			static_call(kvm_x86_msr_filter_changed)(vcpu);
+
+		if (kvm_check_request(KVM_REQ_UPDATE_CPU_DIRTY_LOGGING, vcpu))
+			static_call(kvm_x86_update_cpu_dirty_logging)(vcpu);
 	}
 
 	if (kvm_check_request(KVM_REQ_EVENT, vcpu) || req_int_win ||
@@ -10755,14 +10758,38 @@ int kvm_arch_prepare_memory_region(struct kvm *kvm,
 	return 0;
 }
 
+
+static void kvm_mmu_update_cpu_dirty_logging(struct kvm *kvm, bool enable)
+{
+	struct kvm_arch *ka = &kvm->arch;
+
+	if (!kvm_x86_ops.cpu_dirty_log_size)
+		return;
+
+	if ((enable && ++ka->cpu_dirty_logging_count == 1) ||
+	    (!enable && --ka->cpu_dirty_logging_count == 0))
+		kvm_make_all_cpus_request(kvm, KVM_REQ_UPDATE_CPU_DIRTY_LOGGING);
+
+	WARN_ON_ONCE(ka->cpu_dirty_logging_count < 0);
+}
+
 static void kvm_mmu_slot_apply_flags(struct kvm *kvm,
 				     struct kvm_memory_slot *old,
 				     struct kvm_memory_slot *new,
 				     enum kvm_mr_change change)
 {
+	bool log_dirty_pages = new->flags & KVM_MEM_LOG_DIRTY_PAGES;
+
+	/*
+	 * Update CPU dirty logging if dirty logging is being toggled.  This
+	 * applies to all operations.
+	 */
+	if ((old->flags ^ new->flags) & KVM_MEM_LOG_DIRTY_PAGES)
+		kvm_mmu_update_cpu_dirty_logging(kvm, log_dirty_pages);
+
 	/*
-	 * Nothing to do for RO slots (which can't be dirtied and can't be made
-	 * writable) or CREATE/MOVE/DELETE of a slot.  See comments below.
+	 * Nothing more to do for RO slots (which can't be dirtied and can't be
+	 * made writable) or CREATE/MOVE/DELETE of a slot.  See comments below.
 	 */
 	if ((change != KVM_MR_FLAGS_ONLY) || (new->flags & KVM_MEM_READONLY))
 		return;
@@ -10792,7 +10819,7 @@ static void kvm_mmu_slot_apply_flags(struct kvm *kvm,
 	 * MOVE/DELETE: The old mappings will already have been cleaned up by
 	 *		kvm_arch_flush_shadow_memslot()
 	 */
-	if (!(new->flags & KVM_MEM_LOG_DIRTY_PAGES))
+	if (!log_dirty_pages)
 		kvm_mmu_zap_collapsible_sptes(kvm, new);
 
 	/*
@@ -10823,7 +10850,7 @@ static void kvm_mmu_slot_apply_flags(struct kvm *kvm,
 	 * initial-all-set state.  Otherwise, depending on whether pml
 	 * is enabled the D-bit or the W-bit will be cleared.
 	 */
-	if (new->flags & KVM_MEM_LOG_DIRTY_PAGES) {
+	if (log_dirty_pages) {
 		if (kvm_x86_ops.cpu_dirty_log_size) {
 			if (!kvm_dirty_log_manual_protect_and_init_set(kvm))
 				kvm_mmu_slot_leaf_clear_dirty(kvm, new);