1 files changed, 36 insertions, 9 deletions

diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index b81a9b7c2ca4..93e8120b8021 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -31,6 +31,7 @@
 
 #include <asm/tlbflush.h>
 #include <asm/desc.h>
+#include <asm/kvm_para.h>
 
 #include <asm/virtext.h>
 #include "trace.h"
@@ -133,6 +134,7 @@ struct vcpu_svm {
 
         unsigned int3_injected;
         unsigned long int3_rip;
+        u32 apf_reason;
 };
 
 #define MSR_INVALID                     0xffffffffU
@@ -1383,16 +1385,33 @@ static void svm_set_dr7(struct kvm_vcpu *vcpu, unsigned long value)
 
 static int pf_interception(struct vcpu_svm *svm)
 {
-        u64 fault_address;
+        u64 fault_address = svm->vmcb->control.exit_info_2;
         u32 error_code;
+        int r = 1;
 
-        fault_address  = svm->vmcb->control.exit_info_2;
-        error_code = svm->vmcb->control.exit_info_1;
+        switch (svm->apf_reason) {
+        default:
+                error_code = svm->vmcb->control.exit_info_1;
 
-        trace_kvm_page_fault(fault_address, error_code);
-        if (!npt_enabled && kvm_event_needs_reinjection(&svm->vcpu))
-                kvm_mmu_unprotect_page_virt(&svm->vcpu, fault_address);
-        return kvm_mmu_page_fault(&svm->vcpu, fault_address, error_code);
+                trace_kvm_page_fault(fault_address, error_code);
+                if (!npt_enabled && kvm_event_needs_reinjection(&svm->vcpu))
+                        kvm_mmu_unprotect_page_virt(&svm->vcpu, fault_address);
+                r = kvm_mmu_page_fault(&svm->vcpu, fault_address, error_code);
+                break;
+        case KVM_PV_REASON_PAGE_NOT_PRESENT:
+                svm->apf_reason = 0;
+                local_irq_disable();
+                kvm_async_pf_task_wait(fault_address);
+                local_irq_enable();
+                break;
+        case KVM_PV_REASON_PAGE_READY:
+                svm->apf_reason = 0;
+                local_irq_disable();
+                kvm_async_pf_task_wake(fault_address);
+                local_irq_enable();
+                break;
+        }
+        return r;
 }
 
 static int db_interception(struct vcpu_svm *svm)
@@ -1836,8 +1855,8 @@ static int nested_svm_exit_special(struct vcpu_svm *svm)
                         return NESTED_EXIT_HOST;
                 break;
         case SVM_EXIT_EXCP_BASE + PF_VECTOR:
-                /* When we're shadowing, trap PFs */
-                if (!npt_enabled)
+                /* When we're shadowing, trap PFs, but not async PF */
+                if (!npt_enabled && svm->apf_reason == 0)
                         return NESTED_EXIT_HOST;
                 break;
         case SVM_EXIT_EXCP_BASE + NM_VECTOR:
@@ -1893,6 +1912,10 @@ static int nested_svm_intercept(struct vcpu_svm *svm)
                 u32 excp_bits = 1 << (exit_code - SVM_EXIT_EXCP_BASE);
                 if (svm->nested.intercept_exceptions & excp_bits)
                         vmexit = NESTED_EXIT_DONE;
+                /* async page fault always cause vmexit */
+                else if ((exit_code == SVM_EXIT_EXCP_BASE + PF_VECTOR) &&
+                         svm->apf_reason != 0)
+                        vmexit = NESTED_EXIT_DONE;
                 break;
         }
         case SVM_EXIT_ERR: {
@@ -3414,6 +3437,10 @@ static void svm_vcpu_run(struct kvm_vcpu *vcpu)
 
         svm->next_rip = 0;
 
+        /* if exit due to PF check for async PF */
+        if (svm->vmcb->control.exit_code == SVM_EXIT_EXCP_BASE + PF_VECTOR)
+                svm->apf_reason = kvm_read_and_reset_pf_reason();
+
         if (npt_enabled) {
                 vcpu->arch.regs_avail &= ~(1 << VCPU_EXREG_PDPTR);
                 vcpu->arch.regs_dirty &= ~(1 << VCPU_EXREG_PDPTR);