From 8de48833708a7834f1ba65a80944b1045082553a Mon Sep 17 00:00:00 2001 From: Abel Gordon Date: Thu, 18 Apr 2013 14:37:25 +0300 Subject: [PATCH] KVM: nVMX: Allocate shadow vmcs Allocate a shadow vmcs used by the processor to shadow part of the fields stored in the software defined VMCS12 (let L1 access fields without causing exits). Note we keep a shadow vmcs only for the current vmcs12. Once a vmcs12 becomes non-current, its shadow vmcs is released. Signed-off-by: Abel Gordon Reviewed-by: Orit Wasserman Signed-off-by: Gleb Natapov --- arch/x86/kvm/vmx.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 1cdfb5d7580a..7b27af9a14d8 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -355,6 +355,7 @@ struct nested_vmx { /* The host-usable pointer to the above */ struct page *current_vmcs12_page; struct vmcs12 *current_vmcs12; + struct vmcs *current_shadow_vmcs; /* vmcs02_list cache of VMCSs recently used to run L2 guests */ struct list_head vmcs02_pool; @@ -5527,6 +5528,7 @@ static int handle_vmon(struct kvm_vcpu *vcpu) { struct kvm_segment cs; struct vcpu_vmx *vmx = to_vmx(vcpu); + struct vmcs *shadow_vmcs; /* The Intel VMX Instruction Reference lists a bunch of bits that * are prerequisite to running VMXON, most notably cr4.VMXE must be @@ -5555,6 +5557,16 @@ static int handle_vmon(struct kvm_vcpu *vcpu) skip_emulated_instruction(vcpu); return 1; } + if (enable_shadow_vmcs) { + shadow_vmcs = alloc_vmcs(); + if (!shadow_vmcs) + return -ENOMEM; + /* mark vmcs as shadow */ + shadow_vmcs->revision_id |= (1u << 31); + /* init shadow vmcs */ + vmcs_clear(shadow_vmcs); + vmx->nested.current_shadow_vmcs = shadow_vmcs; + } INIT_LIST_HEAD(&(vmx->nested.vmcs02_pool)); vmx->nested.vmcs02_num = 0; -- GitLab