[v2] KVM: VMX: Execute WBINVD to keep data consistency with assigned devices

Commit Message

Sheng Yang June 25, 2010, 1:08 p.m. UTC

None

Patch

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index a57cdea..1c392c9 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -514,6 +514,8 @@  struct kvm_x86_ops {
 
 	void (*set_supported_cpuid)(u32 func, struct kvm_cpuid_entry2 *entry);
 
+	void (*execute_wbinvd)(struct kvm_vcpu *vcpu);
+
 	const struct trace_print_flags *exit_reasons_str;
 };
 
@@ -571,6 +573,7 @@  void kvm_emulate_cpuid(struct kvm_vcpu *vcpu);
 int kvm_emulate_halt(struct kvm_vcpu *vcpu);
 int emulate_invlpg(struct kvm_vcpu *vcpu, gva_t address);
 int emulate_clts(struct kvm_vcpu *vcpu);
+int emulate_wbinvd(struct kvm_vcpu *vcpu);
 
 void kvm_get_segment(struct kvm_vcpu *vcpu, struct kvm_segment *var, int seg);
 int kvm_load_segment_descriptor(struct kvm_vcpu *vcpu, u16 selector, int seg);
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index abb8cec..085dcb7 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -3138,8 +3138,11 @@  twobyte_insn:
 		emulate_clts(ctxt->vcpu);
 		c->dst.type = OP_NONE;
 		break;
-	case 0x08:		/* invd */
 	case 0x09:		/* wbinvd */
+		emulate_wbinvd(ctxt->vcpu);
+		c->dst.type = OP_NONE;
+		break;
+	case 0x08:		/* invd */
 	case 0x0d:		/* GrpP (prefetch) */
 	case 0x18:		/* Grp16 (prefetch/nop) */
 		c->dst.type = OP_NONE;
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 587b99d..6929da1 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -3424,6 +3424,10 @@  static bool svm_rdtscp_supported(void)
 	return false;
 }
 
+static void svm_execute_wbinvd(struct kvm_vcpu *vcpu)
+{
+}
+
 static void svm_fpu_deactivate(struct kvm_vcpu *vcpu)
 {
 	struct vcpu_svm *svm = to_svm(vcpu);
@@ -3508,6 +3512,8 @@  static struct kvm_x86_ops svm_x86_ops = {
 	.rdtscp_supported = svm_rdtscp_supported,
 
 	.set_supported_cpuid = svm_set_supported_cpuid,
+
+	.execute_wbinvd = svm_execute_wbinvd,
 };
 
 static int __init svm_init(void)
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index e565689..fd6c7e6 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -29,6 +29,7 @@ 
 #include <linux/ftrace_event.h>
 #include <linux/slab.h>
 #include <linux/tboot.h>
+#include <linux/cpumask.h>
 #include "kvm_cache_regs.h"
 #include "x86.h"
 
@@ -170,6 +171,8 @@  struct vcpu_vmx {
 	u32 exit_reason;
 
 	bool rdtscp_enabled;
+
+	cpumask_t wbinvd_dirty_mask;
 };
 
 static inline struct vcpu_vmx *to_vmx(struct kvm_vcpu *vcpu)
@@ -412,6 +415,12 @@  static inline bool cpu_has_virtual_nmis(void)
 	return vmcs_config.pin_based_exec_ctrl & PIN_BASED_VIRTUAL_NMIS;
 }
 
+static inline bool cpu_has_vmx_wbinvd_exit(void)
+{
+	return vmcs_config.cpu_based_2nd_exec_ctrl &
+		SECONDARY_EXEC_WBINVD_EXITING;
+}
+
 static inline bool report_flexpriority(void)
 {
 	return flexpriority_enabled;
@@ -874,6 +883,11 @@  static void vmx_load_host_state(struct vcpu_vmx *vmx)
 	preempt_enable();
 }
 
+static void wbinvd_ipi(void *opaque)
+{
+	wbinvd();
+}
+
 /*
  * Switches to specified vcpu, until a matching vcpu_put(), but assumes
  * vcpu mutex is already taken.
@@ -905,6 +919,15 @@  static void vmx_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
 			 &per_cpu(vcpus_on_cpu, cpu));
 		local_irq_enable();
 
+		/* Address WBINVD may be executed by guest */
+		if (vcpu->kvm->arch.iommu_domain) {
+			if (cpu_has_vmx_wbinvd_exit())
+				cpu_set(cpu, vmx->wbinvd_dirty_mask);
+			else if (vcpu->cpu != -1)
+				smp_call_function_single(vcpu->cpu,
+					wbinvd_ipi, NULL, 1);
+		}
+
 		vcpu->cpu = cpu;
 		/*
 		 * Linux uses per-cpu TSS and GDT, so set these when switching
@@ -3397,10 +3420,26 @@  static int handle_invlpg(struct kvm_vcpu *vcpu)
 	return 1;
 }
 
+static void vmx_execute_wbinvd(struct kvm_vcpu *vcpu)
+{
+	struct vcpu_vmx *vmx = to_vmx(vcpu);
+
+	if (!vcpu->kvm->arch.iommu_domain)
+		return;
+
+	if (cpu_has_vmx_wbinvd_exit()) {
+		smp_call_function_many(&vmx->wbinvd_dirty_mask,
+				wbinvd_ipi, NULL, 1);
+		cpus_clear(vmx->wbinvd_dirty_mask);
+	} else
+		wbinvd();
+
+}
+
 static int handle_wbinvd(struct kvm_vcpu *vcpu)
 {
 	skip_emulated_instruction(vcpu);
-	/* TODO: Add support for VT-d/pass-through device */
+	vmx_execute_wbinvd(vcpu);
 	return 1;
 }
 
@@ -4132,6 +4171,8 @@  static struct kvm_vcpu *vmx_create_vcpu(struct kvm *kvm, unsigned int id)
 			goto free_vmcs;
 	}
 
+	cpus_clear(vmx->wbinvd_dirty_mask);
+
 	return &vmx->vcpu;
 
 free_vmcs:
@@ -4350,6 +4391,8 @@  static struct kvm_x86_ops vmx_x86_ops = {
 	.rdtscp_supported = vmx_rdtscp_supported,
 
 	.set_supported_cpuid = vmx_set_supported_cpuid,
+
+	.execute_wbinvd = vmx_execute_wbinvd,
 };
 
 static int __init vmx_init(void)
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index d0b9252..eba3a2b 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -3650,6 +3650,12 @@  int emulate_invlpg(struct kvm_vcpu *vcpu, gva_t address)
 	return X86EMUL_CONTINUE;
 }
 
+int emulate_wbinvd(struct kvm_vcpu *vcpu)
+{
+	kvm_x86_ops->execute_wbinvd(vcpu);
+	return X86EMUL_CONTINUE;
+}
+
 int emulate_clts(struct kvm_vcpu *vcpu)
 {
 	kvm_x86_ops->set_cr0(vcpu, kvm_read_cr0_bits(vcpu, ~X86_CR0_TS));