KVM: x86: Don't attempt VMWare emulation on #GP with non-zero error code

[linux-2.6-microblaze.git] / arch / x86 / kvm / vmx / vmx.c

diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 4a99be1..d1bac3c 100644 (file)
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -486,6 +486,35 @@ static int hv_remote_flush_tlb(struct kvm *kvm)
        return hv_remote_flush_tlb_with_range(kvm, NULL);
 }
 
+static int hv_enable_direct_tlbflush(struct kvm_vcpu *vcpu)
+{
+       struct hv_enlightened_vmcs *evmcs;
+       struct hv_partition_assist_pg **p_hv_pa_pg =
+                       &vcpu->kvm->arch.hyperv.hv_pa_pg;
+       /*
+        * Synthetic VM-Exit is not enabled in current code and so All
+        * evmcs in singe VM shares same assist page.
+        */
+       if (!*p_hv_pa_pg) {
+               *p_hv_pa_pg = kzalloc(PAGE_SIZE, GFP_KERNEL);
+               if (!*p_hv_pa_pg)
+                       return -ENOMEM;
+               pr_debug("KVM: Hyper-V: allocated PA_PG for %llx\n",
+                      (u64)&vcpu->kvm);
+       }
+
+       evmcs = (struct hv_enlightened_vmcs *)to_vmx(vcpu)->loaded_vmcs->vmcs;
+
+       evmcs->partition_assist_page =
+               __pa(*p_hv_pa_pg);
+       evmcs->hv_vm_id = (u64)vcpu->kvm;
+       evmcs->hv_enlightenments_control.nested_flush_hypercall = 1;
+
+       pr_debug("KVM: Hyper-V: enabled DIRECT flush for %llx\n",
+                (u64)vcpu->kvm);
+       return 0;
+}
+
 #endif /* IS_ENABLED(CONFIG_HYPERV) */
 
 /*
@@ -4510,12 +4539,22 @@ static int handle_exception_nmi(struct kvm_vcpu *vcpu)
 
        if (!vmx->rmode.vm86_active && is_gp_fault(intr_info)) {
                WARN_ON_ONCE(!enable_vmware_backdoor);
+
+               /*
+                * VMware backdoor emulation on #GP interception only handles
+                * IN{S}, OUT{S}, and RDPMC, none of which generate a non-zero
+                * error code on #GP.
+                */
+               if (error_code) {
+                       kvm_queue_exception_e(vcpu, GP_VECTOR, error_code);
+                       return 1;
+               }
                er = kvm_emulate_instruction(vcpu,
                        EMULTYPE_VMWARE | EMULTYPE_NO_UD_ON_FAIL);
                if (er == EMULATE_USER_EXIT)
                        return 0;
                else if (er != EMULATE_DONE)
-                       kvm_queue_exception_e(vcpu, GP_VECTOR, error_code);
+                       kvm_queue_exception_e(vcpu, GP_VECTOR, 0);
                return 1;
        }
 
@@ -5172,7 +5211,6 @@ static int handle_invalid_guest_state(struct kvm_vcpu *vcpu)
                err = kvm_emulate_instruction(vcpu, 0);
 
                if (err == EMULATE_USER_EXIT) {
-                       ++vcpu->stat.mmio_exits;
                        ret = 0;
                        goto out;
                }
@@ -6511,6 +6549,9 @@ static void vmx_vcpu_run(struct kvm_vcpu *vcpu)
                current_evmcs->hv_clean_fields |=
                        HV_VMX_ENLIGHTENED_CLEAN_FIELD_ALL;
 
+       if (static_branch_unlikely(&enable_evmcs))
+               current_evmcs->hv_vp_id = vcpu->arch.hyperv.vp_index;
+
        /* MSR_IA32_DEBUGCTLMSR is zeroed on vmexit. Restore it if needed */
        if (vmx->host_debugctlmsr)
                update_debugctlmsr(vmx->host_debugctlmsr);
@@ -6578,6 +6619,7 @@ static struct kvm *vmx_vm_alloc(void)
 
 static void vmx_vm_free(struct kvm *kvm)
 {
+       kfree(kvm->arch.hyperv.hv_pa_pg);
        vfree(to_kvm_vmx(kvm));
 }
 
@@ -7837,6 +7879,7 @@ static void vmx_exit(void)
                        if (!vp_ap)
                                continue;
 
+                       vp_ap->nested_control.features.directhypercall = 0;
                        vp_ap->current_nested_vmcs = 0;
                        vp_ap->enlighten_vmentry = 0;
                }
@@ -7876,6 +7919,11 @@ static int __init vmx_init(void)
                        pr_info("KVM: vmx: using Hyper-V Enlightened VMCS\n");
                        static_branch_enable(&enable_evmcs);
                }
+
+               if (ms_hyperv.nested_features & HV_X64_NESTED_DIRECT_FLUSH)
+                       vmx_x86_ops.enable_direct_tlbflush
+                               = hv_enable_direct_tlbflush;
+
        } else {
                enlightened_vmcs = false;
        }