path: root/virt/kvm/kvm_main.c
diff options
authorJunaid Shahid <junaids@google.com>2018-06-27 14:59:11 -0700
committerPaolo Bonzini <pbonzini@redhat.com>2018-08-06 17:58:54 +0200
commit50c28f21d045dde8c52548f8482d456b3f0956f5 (patch)
treef0c046a9dfba1a1b0aec3b286faed82df10dc92e /virt/kvm/kvm_main.c
parent1c53da3fa3a333eb15ee5a154700e75d135c21c8 (diff)
kvm: x86: Use fast CR3 switch for nested VMX
Use the fast CR3 switch mechanism to locklessly change the MMU root page when switching between L1 and L2. The switch from L2 to L1 should always go through the fast path, while the switch from L1 to L2 should go through the fast path if L1's CR3/EPTP for L2 hasn't changed since the last time. Signed-off-by: Junaid Shahid <junaids@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'virt/kvm/kvm_main.c')
1 files changed, 10 insertions, 4 deletions
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index f519eb8d06b1..8f461e0ed382 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -2127,16 +2127,22 @@ static void shrink_halt_poll_ns(struct kvm_vcpu *vcpu)
static int kvm_vcpu_check_block(struct kvm_vcpu *vcpu)
+ int ret = -EINTR;
+ int idx = srcu_read_lock(&vcpu->kvm->srcu);
if (kvm_arch_vcpu_runnable(vcpu)) {
kvm_make_request(KVM_REQ_UNHALT, vcpu);
- return -EINTR;
+ goto out;
if (kvm_cpu_has_pending_timer(vcpu))
- return -EINTR;
+ goto out;
if (signal_pending(current))
- return -EINTR;
+ goto out;
- return 0;
+ ret = 0;
+ srcu_read_unlock(&vcpu->kvm->srcu, idx);
+ return ret;