From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Tim Chen <tim.c.chen@linux.intel.com>
Date: Fri, 13 Oct 2017 14:31:46 -0700
Subject: [PATCH] x86/kvm: Set IBPB when switching VM
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

CVE-2017-5753
CVE-2017-5715

Set IBPB (Indirect branch prediction barrier) when switching VM.

Signed-off-by: Tim Chen <tim.c.chen@linux.intel.com>
Signed-off-by: Andy Whitcroft <apw@canonical.com>
Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
(cherry picked from commit 665076ad780e8620505c742cfcb4b0f3fb99324a)
Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
---
 arch/x86/kvm/vmx.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index daff9962c90a..8df195bbb41d 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -1488,6 +1488,7 @@ static void vmcs_load(struct vmcs *vmcs)
 	if (error)
 		printk(KERN_ERR "kvm: vmptrld %p/%llx failed\n",
 		       vmcs, phys_addr);
+
 }
 
 #ifdef CONFIG_KEXEC_CORE
@@ -2268,6 +2269,8 @@ static void vmx_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
 	if (per_cpu(current_vmcs, cpu) != vmx->loaded_vmcs->vmcs) {
 		per_cpu(current_vmcs, cpu) = vmx->loaded_vmcs->vmcs;
 		vmcs_load(vmx->loaded_vmcs->vmcs);
+		if (boot_cpu_has(X86_FEATURE_SPEC_CTRL))
+			native_wrmsrl(MSR_IA32_PRED_CMD, FEATURE_SET_IBPB);
 	}
 
 	if (!already_loaded) {
-- 
2.14.2

