From f24632475d4ffed5626abbfab7ef30a128dd1474 Mon Sep 17 00:00:00 2001 From: Bruce Rogers Date: Thu, 28 Apr 2016 14:49:21 -0600 Subject: [PATCH] KVM: x86: fix ordering of cr0 initialization code in vmx_cpu_reset MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Commit d28bc9dd25ce reversed the order of two lines which initialize cr0, allowing the current (old) cr0 value to mess up vcpu initialization. This was observed in the checks for cr0 X86_CR0_WP bit in the context of kvm_mmu_reset_context(). Besides, setting vcpu->arch.cr0 after vmx_set_cr0() is completely redundant. Change the order back to ensure proper vcpu initialization. The combination of booting with ovmf firmware when guest vcpus > 1 and kvm's ept=N option being set results in a VM-entry failure. This patch fixes that. Fixes: d28bc9dd25ce ("KVM: x86: INIT and reset sequences are different") Cc: stable@vger.kernel.org Signed-off-by: Bruce Rogers Signed-off-by: Radim Krčmář --- arch/x86/kvm/vmx.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index ee1c8a93871c..ab4a387b98b1 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -5046,8 +5046,8 @@ static void vmx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event) vmcs_write16(VIRTUAL_PROCESSOR_ID, vmx->vpid); cr0 = X86_CR0_NW | X86_CR0_CD | X86_CR0_ET; - vmx_set_cr0(vcpu, cr0); /* enter rmode */ vmx->vcpu.arch.cr0 = cr0; + vmx_set_cr0(vcpu, cr0); /* enter rmode */ vmx_set_cr4(vcpu, 0); vmx_set_efer(vcpu, 0); vmx_fpu_activate(vcpu); -- 2.11.0