From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sheng Yang Subject: [PATCH] KVM: VMX: Fix 32bit Windows blue screen with EPT Date: Thu, 30 Dec 2010 16:35:59 +0800 Message-ID: <1293698159-30452-1-git-send-email-sheng@linux.intel.com> Cc: kvm@vger.kernel.org, Sheng Yang To: Avi Kivity , Marcelo Tosatti Return-path: Received: from mga02.intel.com ([134.134.136.20]:63413 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751903Ab0L3Ie3 (ORCPT ); Thu, 30 Dec 2010 03:34:29 -0500 Sender: kvm-owner@vger.kernel.org List-ID: After CR0 is changed during VMExit, the result of kvm_read_cr3() may be different. Commit d95bfcdd7cda4dfdac9588e684bc7c75794a075e "KVM: Fetch guest cr3 from hardware on demand" caused 32bit Windows guest blue screen when using with EPT. This patch fixes it by decache CR3 before CR0 change, for both paging to nonpaging, and nonpaging to paging switch. Signed-off-by: Sheng Yang --- But I haven't found the exactly point affected by this, any clue? arch/x86/kvm/vmx.c | 6 +----- 1 files changed, 1 insertions(+), 5 deletions(-) diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index f107315..0b8cfc1 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -1921,8 +1921,7 @@ static void ept_update_paging_mode_cr0(unsigned long *hw_cr0, unsigned long cr0, struct kvm_vcpu *vcpu) { - ulong cr3; - + kvm_read_cr3(vcpu); if (!(cr0 & X86_CR0_PG)) { /* From paging/starting to nonpaging */ vmcs_write32(CPU_BASED_VM_EXEC_CONTROL, @@ -1937,11 +1936,8 @@ static void ept_update_paging_mode_cr0(unsigned long *hw_cr0, vmcs_read32(CPU_BASED_VM_EXEC_CONTROL) & ~(CPU_BASED_CR3_LOAD_EXITING | CPU_BASED_CR3_STORE_EXITING)); - /* Must fetch cr3 before updating cr0 */ - cr3 = kvm_read_cr3(vcpu); vcpu->arch.cr0 = cr0; vmx_set_cr4(vcpu, kvm_read_cr4(vcpu)); - vmx_set_cr3(vcpu, cr3); } if (!(cr0 & X86_CR0_WP)) -- 1.7.0.1